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Math 7 - Module 1D - Lesson 20

Added Jan 26, 2021 •

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How to make a Scale Drawing. Measure and Record all sides. Calculate new proportional corresponding sides using the Scale Factor Calculate Scale Drawing Area using the Area Factor

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720 exercise in creating a scale drawing what is a scale drawing scale drawing what to do when one more too much a scale drawing is also known as a proportional drawing this can't be done already a proportional drawing tattoo cold or it's dry let's switch over to another one when it's go wish personal drawing all measures are proportional to original so all your messages are proportional to the original she got a drawing and a scale drawings just proportional there's nothing there are two types of scale put it in the chat who remembers what the two scales are what are the two types a skill try to take back to the beginning the first lesson of module 1 d good and correct I got one two people three excellent I need to I want five of you guys I need two more people what are the two things alright this person says alright scale bigger scale smaller that is the operation what is the actual vocabulary word to describe the noun what are the scaling bigger ions what are the scaling smaller items what are they called you need to know this vocabulary is key very good I like that you said that but what are those so for the rest of yours I gave you a hint that this person right here reading make make bigger makes how is the same thing that person just said what's the vocabulary word though I got all right all right I got four people I need one more person to tell me what it is are you at what's the other half that's make smaller what's make beard called haha so that's why you guys got to get this stuff vocabulary super important so yes there are two types of scale drawing usually when you make a drive using make it smaller we take us something we see and make it smaller that's called a reduction for the most part all scale drawings are reduction very few times do we make an enlargement but there are times when you do  when you enlarge a photo you make a poster out of it for the most part we take something but likes is a poster and making into something that's smaller BK around so an enlargement and a reduction and here's the thing if you don't enlarge it correctly everything's all stretched out or squeeze down so that's not proportional so that's proportion to the original but you got to think though we don't start with a C call Brian so there's one thing you need to know that you had before what's not a scale drawing then is called a sketch sketch drawing it's not accurate so that's a nice way of saying it not an accurate not important not proportional or not accurate in terms of English you got to think I always refer thing relate all your math problems to an essay in math and Matthew have an essay but before you write an essay your teacher always makes me do either an outline or rough draft and that's what a sketch is you throw things where they might go and it might not clean but you have an idea the scale drawing is when it's all cleaned up and perfect when you turn it in so let's think about it like that so it's sketch drawing is like an outline an outline of an essay a scale drawing is pretty much is the product what you turn in so understand schedule something just put together you don't even care if it looks right you just put it in its place will do a sketch in a second and then we'll do the scale drawing cuz that's what we're going to change us we're going to tennis we're going to change a sketch into an accurate drawing all right so today you will be a your knowledge from working with scale drawings to create a floor plan for your idea of the dream classroom all right but what's a floor plan a floor plan is like an overhead view over head View can also be called a top view top view diagram of air best way I can describe it I've been using I've been using Zelda when you go in the dungeon pack even when you don't go to the dungeon you press the pause button start button you get the map and the map is a top down view a top view or an overhead view yet you don't see all the detail you don't see at the angle but you see everything like you're looking over it's like a maze you're looking on top of the maze so that's pretty much what a floor plan is you're looking above think about yourself as a deity your floating above your you know what you use your a deity of the area or I can use a three letter word psych NDTV I know can't use that word so you're a deity floating above your people's but the thing is you don't see that you don't see how tall they are they looks like a seed looks like dots moving around flat you can look through the roof cuz he had like x-ray vision but you don't see you like walls you see lions and looks like a maze that's what that is right there all right so what are we going to do Explorer challenge your dream class measure all this stuff so guideline this is this is an exercise you would have done in class you would have got out of her chairs but since we're all trapped at home for now until maybe earliest end of March yeah then you guys are sitting in your super comfortable classroom chairs lying down sleeping on your school desks we passed out look at her yawning already she be asleep drooling on my school desk yes so but but in class we would have got enough today measured all this stuff right here so take the measurements all students will work with the perimeter of the classroom as well as the doors and windows gives students the dimensions of the room has students use table provided down here are the measurements when I do all that together I see she's not paying attention she doesn't get it but remember she can't read yours we're not talking about Alabama yet now alright let's get on with this so we're going to create your dream your dream used furniture we don't have a Furniture catalog so we're not going to bother with that we're going to make a sketch of a classroom that's the next page and then we're going to determine the scale and calculate scale drawing lengths and widths so we're going to make ask the classroom at least my classroom some you guys were in it last year during the after-school program when they're and trashed it so you had an idea what my classroom looks like and then we're going to pretty much put measurements on there and then we're going to go on the 3rd and make a scale drawing accurate so we're going to forget this for now but let's look at it though look at it first so we got class and perimeter Windows door additional Furniture here's what we put down let's student desk student chair and here's the thing we could group this stuff together if we want that's fine I'll put the video up later on tonight let's put a whiteboard it'll be easier this right here is if you waste time to tell you I'm going to switch it up student desks I'm going to end up calling a student group all right so let's look at em we would have measured in real yes you're fine of the video what we would look we look at the actual length we live in the class I would have had a tape measure a measuring tape and we would have together measure the length of the classroom and the Wolf the classroom so we can find the perimeter we measure how long the window is but here's the thing we're only going to put it in one of these and I'll show you why in a second same thing how why I want you know how wide is a door the measurements of a desk student chair the Whiteboard and trim a student group will keep it simple for today and then we're going to figure out the new measurements We're Going Back review how do you find the new measurements how do you find the new measurements so even though up here it would have said each pair of students will determine its own scale we're not going to do that we're going all use the same scale and we're going to keep it simple green to keep it simple so cuz you know I want to do without a calculator so we're all going to use the same scale factor scale factor so I wrote the word scale factor but remember we are lazy mathematicians use the easy way to write scale factor SF that's the whole thing about math and always do shortcuts learn to do short test scale factor equals 1/10 so whatever measure we're going to do we're going to shrink it down 10 times ruined it rephrase it how did I just said we're going to shrink it Down based on the information I gave you how do you know this is a reduction how do you know because of the scale factor how do you know it's a reduction that's one key fact I need to know for test at 2 weeks how do you know you have a reduction if you have the scale factor how do you know it's a reduction all right one good answer one one person that was quick you're thinking you are remembering how do we know we have a reduction based on the scale factor I would like three more answers before I move on I got one and that person you were totally correct pat yourself on the back no no don't even try and pass yourself on the back you didn't answer that see out pat yourself on the back you can see set myself on the back how do you know we have a reduction based on this why does this scale factor say we have a reduction and we are reducing our measurements by 10 times drinking it how do you know we're drinking it 2 second person your answer is very close it's like one of those not enough detail not enough information answers but you finish that finish giving me a full idea you be correct all right one and a half people I don't want to wait in will you know you have a reduction because your scale factor is less than one you got to think something is bigger we say it's twice as big three times as big no matter what it's bigger than one this right here a fraction is less than 1 so it doesn't grow it shrinks it shrinks this many time so when you have an enlargement you multiply you still multiply but you got to think of fractions another way of writing division so technically you divide all right so let's move on call before we move on. This formula so once we find our original measurements you multiply with the scale factor you get the new measurements the original times the scale factor equals the new measurement yes you can't hurry up and come back on so turn to the second page right now or flip it or if you got no paper don't worry you don't need paper cuz it's like space the right here use the space to sketch the classroom perimeter draw out your ideas play with the placement of the furniture store besides Alabama is Alabama's Western you know I wonder if Alabama gear is but know who knows what is a typical shape of a classroom didn't I want to know your basic shapes skills if you can what is the basic shape of a classroom I knew you one of you would say it no it's not a circle there's no set it was there is such encircle classroom it is not a circle yes you are correct Square there are square crowded classrooms but it's not really Square say there's a better square is a specific example of this other shape square is closed what rectangle rectangle correct someone said a triangle there are special schools that have triangular shaped rooms but no I said typical which means in general square square doesn't really fit things right we'll go over that the next couple days about why a rectangle is better than a square so sketch a square alright notice it's not perfect it's kind of ugly but you get the idea to recognize what makes this a sketch a sketch means you do it really quick and it's just to put down your ideas that's what we call it an outline sketches an outline all your stuff so for those you guys that ransacked my room last year when you guys are part of the after-school program alright where was where was my my room is next to my room was next to the gate so that way he the middle school game and because of last class Gustavo said the street was Lusk I thought it was another shut that was apgar I don't know but he said it was lust but we're in a simple sentence the Middle School gate that's my classroom is right here next to here would be the other class and that was mr. flemister across here was the school the middle school office miseno's classroom is right here next door to me was mr. Lee and right now I know was the bathrooms right there that's what my classroom look like so now that you know where it is we had right here was the door I was put that there door then we had the big window that all the Portables at in medical but that their window and then down here are the other opposite side there was a window I was the same other window but let's just right window Atlantis look at all the other stuff you want to put in we had the Whiteboard the way board was against this wall right here and then we're not going to measure but let's just put it in anyways for now just to kind of get an idea with a yes someone it's a map a map is a top of you noticed I'm a plea means here you are a DD floating around here's you you're the X you're floating around notice you look straight down you're looking straight down that's what a map is we don't know how tall it is we have the edges the outline of everything x-cellent good job good job but yes you remembered bottom left right here so teachers depending Messina liked her teacher desk light by the door I don't like that and I'll tell you why is when you get before you Middle School is messed up your lunch you were able to walk around and you know I do all that so during lunch time in a people would come in here hey we bother her but I was smart hairless for the cabinet's forget it with the cabinets we're not going to cabinets I put my teacher desk down here let's choose another color for that alright by then it was a weird kind of you shape horseshoe-shaped it wasn't your teacher desk and I put my table so cuz the whole thing is right here if I had it right here next to this when do you come in and see me all you me during my lunch while I'm trying to eat no so see who would bother me a lot Alabama would definitely bother me telling me all about Alabama but right here when you put the desk right here strategically you guys came in and open the door during less you be like it's going to say hello and then you realize to get to me you'd have to walk all the way over here during lunch you all become for some reason lazy so you wouldn't walk here but if my desk was here you taken 2 steps in what are you eating or did you see this all do you know if I got my new crush hahaha surgery and then if it's this far you wouldn't even have a conversation with me cuz it be too far for you to walk that's why I like my desk are but then yes and then you saw other teachers now the next thing of the student desks how do you place it yes mine were placed in groups of four so I would put forever mine would always be grouped up is if I didn't Rose or columns that's just too much placement two groups of four four tables at put together and you know you'd have that in that has you know right there their they're there and then I have one next to my desk I would make all these people hand out on my papers these people right here I put close enough to the annoyed me these people right here and put by the door because I need fresh air and they they maybe by the door to keep the air fresh in the room haha so they were right here I had 24 student desks in my classroom that we also had chairs you got to take this what teachers do all the time that's how we we pretty much make groups we make we pretty much make a little yes yes good you saw some of your teachers taking roll taking attendance on a piece of paper and they would just mark it everyday good same thing we do this so we organized our classroom we lay it out so I had my little teacher desk right here where the projector cuz I had a cable connected to projector right here so would you know right there so I have a table to work on right here and I would have to lonely desk next to me because you would have to sit next to me if you annoyed everyone else and you can keep yourself Isaac Woodbridge everybody grab their pads eat their food like he's doing right now cuz right now he's not paying attention he's watching some show look at him Chomp Chomp Chomp he's eating goldfish looks like Cheetos to me is watching a show commuted me look at it don't worry about them thank you for letting me know now there's placement of chairs you got to think these people here's a whiteboard I can't put the chairs right here because they won't be able to see that's why these people right here would have to sit right here so we have chairs right there little square put them in as chairs and then these people to look straight in I can have him right there these people right here had the hardest time seeing so I put them right here no this person right here there's no way again they can't have the back to that you can't have that chair right there they can't see them so let me cry set up and I put the chair right here and this person will be seated right here same thing as the same setup but remember why you guys know that it was the wipers that you to whiteboards connected as one and the projector would always be projected on only half the projection screen so even though the person we facing this way no cuz I need to be looking at this white part of the Whiteboard this person right here would no longer be here and be easier for this person to sit right there and look right there same thing this person right here this person now though could sit here if they sat here they have to turn around look this way and they only need to turn around a little bit if they sat here and then this person is still looking forward right here on this table same thing right here this person could sit right here and now they had to turn around so it'd be better for them to sit right here and both of these people right here be better cuz they look this way this person look straight ahead this right here I would have both of them cuz looking forward is easy right here and then I would set it up again like this and said that begin like this so look that right let's see looking straight down set up like this and then this person would be right here and this person be right here this person right here usually does most of my paper handout notice all the chair groups are almost different this is the same this is the same this is the same but these are kind of different the only chair that's always in the same spot as I see two people person you're sitting on this corner noticed all the groups of a person sitting on the bottom left corner and all of them have someone seated at the same part on the upper right mother's upper right see it's just these two chairs we had to move around depending on where you were that's the thing about groups someone's always turn around all right but this is the sketch nothing special but let's put in measurements I had to look it up this last night cuz the first class I did it and I all my measurements were off but I was actually pretty close so a portable at school is 24 4 feet long I guess 25 that first day I just made up some numbers 24 ft long actually Gustavo was even a bigger they're denying he went super detail is 24 and a half 24.5 ft long I just wrote 24 see what the other measurements were and it was 44 ft why lawn alright 44 ft I'm going to stop for a second how come I didn't write the other two so that's how come I didn't put a number up here and how come I did not put a number right there how come I only work 24.5 right here in 44 right there how come I Didn't Do It on the other side type in your gut why did I not do that for the other side's see how Ro 24.5 ft right here by then label the other side I see Hyrule 44 feet for this side how come I did not this side and how come I did not lay with the other I don't care no I don't understand that I don't care two of you wrote that because the other sides are the same as each other I I do like that but it's not truly accurate is that was an essay that was a sentence in your essay I wrote it I would have wrote underlined it with red marker and I were to be more specific what are you talking about and some he doesn't like what so that's the whole thing about explanation now the next thing right here and plus you said we are lazy yes that is the number one point I only wrote it right here in here because yes I told you guys be lazy be lazy in the sense to Safeway but versus the other part when I said you're not specific so there's a little different there's that little thin line between being lazy and being fully correct so lazy you could save time you don't need to do being correct means be specific he said okay 3 and 4 you said the same thing two more people trying to do all four people said the other sides are the same same as what be specific so the definition of a rectangle opposite sides of a rectangle are equal so the opposite side for this 44 is the side with the Whiteboard that's also 44 but you don't need to write it just went 4.5 ft is opposite this side so this whole thing is 24.5 ft you don't need to write it because we can be lazy but opposite sides of a rectangle are equal see that right there specific you can't see because the other what's the other that's why in an essay your teacher and Mark you down for that cuz they want you to tell you specific certain things where as being lazy. 4444 we don't have to write it we know it so lazy versus goodly this is good lazy right here versus you know being specific so this right here here to hear is 24.5 ft here is 44 feet now is put in other measurements the door the door is 3 feet the window AR 6.5 ft long and this is another reason why we didn't I didn't put it down here cuz look look at this number now it gets mixed I hear these you can see super clear they're separated look at this all right that 6.5 ft and kind of crunched up against their the Whiteboard a whiteboard is 16 ft long and yellow 60 ft long will that's not too long the whole room is 44 so not too much your tables do student desks your student asks so here to hear is 2.5 here to hear is 2.5 here to hear is 2.5 if you have that if you have that good excellent but that's for all four sides though what is the length of here to hear though what is the length of that one type it in you see how I got this right here each little desk remember I put for student desks together that's 2.5 that stupid just to show you different size cuz I don't want to get in the way of the chair 30 here is 2.5 here to hear is 2.5 and it's the same setup what will be the length from here to here what number is that type it in so I know remember how I said Lego math good you are right about the Lego mask I got one person understood is super quick how long is this what's the line from here to hear it from here to hear is 2.5 and here to here is two and a half feet what do I put them together put them together Legos here to hear is 2.5 ft. 2.5 ft here to hear yes don't know I understood that good good good good traction there so yes 55 ft long yeah I can I get why you said that it's not 12 and 1/2 but just talked about the lengths here to here so good so 2.5 and put them together like Legos 5 seat good so you get a giant 5-foot Square now I'm going to give you the chairs though each chair is 1.5 1.5 they're all the same yeah you got a foot and a half to sit down on a making them Squares even though they should be squares it just makes it easier don't notice this right here on the chair I put units on both sides cuz there's they're stuck in the middle but along the edge look at this I don't care how tall the door is unlocked and how wide it is as if I'm looking straight down I don't see how tall it is all I see is how wide now before we move which do you want to call the length I need a hero Choice do you want the 44 to be the length or the 24.5 to be the length to remember you have length and width and those don't matter you just need to name it okay how you persantine 44444 is the link so before we move on let's write that down so we don't get lost this is the length this is the width take a second and label that cuz if you mix these up somebody said so we can switch these if you want yes but you have to do it beforehand so we went nice going up and down what's going left and right but you can switch it in Geometry that's why they're more specific instead of the word length and width cuz which ones which which one that's personal choice but in geometry we called the one on the bottom or the top bottom and top are called basis base plural basis b a s e s so the bottom and size of the base and the up-and-down are called the height so up and down his height that's why the base and height instead of length and width but we'll get there later but let's look at this right here listen to the difference so we're going to look at area right now area and perimeter the perimeter perimeter is total length and here's a thing we have length but we got with that's why I use this instead total distance books don't use the word lengths that use the word distance because if he if you get it confused you're only looking at length width is a links to it's a specific length but that's how use the word distance the perimeter total distance around an object it's not always a rectangle you might have a triangle you might have a trapezoid a parallelogram yes even a circle but in a circle the perimeter is called the circumference when I dealing with that right now will do that later so we're just talking things with angles right here so angle does matter a little bit when we get two more specific geometry stuff but the angle here's a big rectangle the rainbow angles the angles are 90° angles right angle they're all 90° perfect square I don't want to use that must go black does not want to mix it up with the chair that's not a chair all your Corners are perfectly where is what they call it a right angle is a square angle alright the perimeter is a total length of the distance around an object so there's a lot of different formulas and then let's go right here area area is the amount Square units that can fit inside an object this definition confuses a lot of people but we'll go over it so where does area and perimeter perimeter super easy so does anybody remember the perimeter formula for a rectangle there's actually three just give me one if you know one of them does anybody remember the perimeter formula for a rectangle I'll write down all three and show you that it's the same I just want one you're correct I'm going to write down this one first, write down this one last to put in the back so this person said perimeter equals 2L + 2W the perimeter is 2 times the low plus two times the width where does this come from it came from this first one the perimeter of a rectangle so let's go this way I'll let's go this way thanks + width + length + width the length plus the width plus the length plus the wits let's put that in the length is what 44 perimeter equals 44 + 24.5 + 44 + 24.52 write even I'm he's saying that my mouth is dry. What about that now let me choose a different color so we can separate them I was just use a drug to me there was another formula which most some you guys knew perimeter is also 2 time double the length Plus. this one I think is the easiest one this all we did notice L + w l + W that's just that twice and then if we distribute some guys learn distribution that's this right here to x out 2 l x w w we distributed let's write this one on PC equals 2 * 44 + 24.5 oh I can ask play some pretty quick 2 * 44 + 2440 + 20 + 64 + 4 + 868.5 and then all I do is double that why I can't do that right now let's do this one perimeter equals 2 times my length which is 44 + 2 * my width 24.5 double 4488 double 24.524 + 24 + 4840 88 + 4980 + 40 is 120 9 + 7 is 17 100 37 let's look at 60 + 60 is 120 8 of 8 is 16 1/6 + 16 + 136 + 25.5 + 137 something and this right here I would just have to add one to the other to the other which one's better there are the same piano you just double it now before I move on does anyone know formula I want the Formula First what is the area of a rectangle does anybody remember the formula to the area of a rectangle type it in the chat if you know how to find the area of wrecked I do not want the number I just want the formula how do you find the area of any rectangle you are correct you are correct come on I think you learned this in for 3 when you did bass it basic word problems and they gave you a picture what is the area of a rectangle I know two more of you guys more than two of you guys know this yes go more than three of you guys I'll just type in what is the area of a rectangle nice all right. Okay to stop now okay that's one thank you 8th of you good job the area of a rectangle is length times width notice how they're different we have a length and a width here too but we're multiplying instead of adding and multiplying length times width or length again was 44 on our with was 24.5 so how many MLS teams are calculator how do I dim this what is a 44 * 24.5 1078 look at the so these are two different versions of the perimeter 137 but then the area is so much bigger 1078 yeah so lot of I don't understand what a perimeter is and is super easy to explain how I explain it in class think about a paperclip if it was my class these fools would go around in my desk and steal all my supplies my paper clips cuz I would find them see all you guys are smiling cuz you know you were those people you would take my paper clips and unravel them and straighten them out and planted  me off instead of a paperclip what do I have a bunch of a I don't know metal sticks annoying and then where would I find those metal sticks on the top of my ceiling cuz you playing it up there and get it stuck like pencils all you guys that are laughing are the ones that did it in all the class I hate you cuz those paper clips aren't cheap man that's why I go to Daiso now get those generic ones that snap the horrible horrible paper clips cheap worse than Dollar Store anyways so just imagine my perimeter so the Perimeter Pointe adding up all the sides just imagine if I took the paper clip and I unraveled it stop talking about going away on the building I just have a line so a perimeters actually imagine the length of all your size as one giant line so we start at 0 and our first silent was what 44 and then we went to the next short side was 24.5 and then we went to the other side which was another 44 more and then 24.5 if we add all the sorry you to decide my fantasy here to here 424.5 here to hear is 44 more beautiful. That's what your perimeter is what if you took what is missile defense and instead of having your fence go around and make rectangle you unfolded it in may just a wall one long fence without having Corner that's what a perimeter is you're just going around and see how long is it straight that's what your perimeter is going around the block what is the perimeter of the block if you guys are doing a track and field of running on the track could run the perimeter of the track you can't go in the middle cuz that would be cheating and some of you guys tried to do last year in your mile Sergeant got you haha you going to go a mile and just go from here to here no you didn't run your mile so inside that's called the area around the fencing that's the perimeter so area though yeah Square inside the length and width what does that mean though so I'm going to draw another sketch small rectangle but it represents that one so 44 24.5 look at this right here I got this. That's what a sketches a sketches just something to give you an idea now instead of seeing this as 44 long see it as 44 Rose 44 equal rows and then you'd end up with the 44 so we get one 223 goes on 4 5 6 and 44 so we have 44 Rose that's 44 think about this you would have 24.5 columns let's go I would have 2 and it go all the way there 24.5 alright so look at this right here it's like a multiplication table I got to across three 2 * 3 I got 6 little cubes here area 44 * 24.5 this last cube is that's how many little squares that can it in there so it's square units this right here is called a square unit it is a one by one 1 * 1 equals one that's why it's called a square unit square feet square feet whatever units were using so square inches square feet to square meters always pay attention to the units good good catch so this right here I got lazy and messed up other teachers would have marked you points are did you always want to have your measurements noticed right here perimeter we would flatten it out to a straight line so that's just how long is 137 ft but when were talking about the area how many little squares can you fit in that's why it's called square feet show inside the 44 x 24 and 1/2 you could fit 1078 little squares in perfectly that's what area means how many little squares in their purses how long is it square units someone just wrote where would you see square feet for all you guys that moved during the because you give there's a lot more places to rent and cheap now look at on a piece of paper is how big the play and what is it measured in square feet so how to find the area so the area in real life of my classroom is 1078 square feet that's actually pretty big man what's the average size of a apartment that's pretty huge pretty huge so yeah this right here people are paying in let's average price of Bay Area a house that's almost 1100 square feet not. That does not include the backyard just a house where you live inside this right here is about $500,000 that's what people are paying for yeah I know right cuz you got to send you had a kitchen small kitchen you can fit two bedrooms two regular sized bedrooms you got ROK size living room yellow for 4 living room kitchen to bedroom and the bathroom just in a little bathroom in there a little shower yeah that's $500,000 that's the classroom yeah that's what yes some people moving it they pay attention to how big these are so that's what we're doing right here 24 plan so let's translate this stuff now we could go to Pages we could go to the last page the fourth page classroom what's the actual area of the classroom it was 44 x 20 4.5 that equals 1000 78 square feet when we do a scale drawing scale drawing area no it's going to be smaller but how much smaller and I want to jump ahead you got to remember we can actually figure this out so area Factor equals scale factor x scale factor what's another way of writing scale factor r squared we cannot you calculate once we have our scale factor we can actually calculate our area without even drawing it and we might do that first we get there fast enough will save that little piece out where is this that was the last page page number for so this is the thing about area actual area that bathroom scale drawing area where she going to find it actually we can't find it because this are scale factor is 110th right so the area Factor the area Factor should be 1/10 * 1/10 which is another way of saying 1 / 10 squared that equals 1 over 100 how do you find your new area how do you find your new area you take your old number it's just like a skillet OG times the area Factor equals the new area so we're going to do our sketch in a second but let's see let's find the sketch area without even drawing the let's find the scale area without even doing the scale drawing sorrow G area was 10000 1078 m1078 and we found our area factor is when you're doing area you got to remember that use the area that's not a plus it's X thank you for correcting me good job supposed to be x o g x area Factory was in area faster is 101-100 and then since that's not a fraction we could put it over a 1 so we got 1078 / 1 let's go cheat again he's our pact of the time to tell you it's a desolate here's the decimal we need to move the decimal back over twice that's a shortcut you want to get rid of zeros so they are here here's a decimal place here's a dozen the shortcut if you guys don't remember this if you've never been talked this so when you have zeros in back you can always divide by moving the decimal is over let's this 1 2 1 2 10.78 should be our new area when we multiply it let's do a calculator 1078 / 101078 / 100 10.78 1078 * 1/100 cuz why do guys got slots haha why do I divide my mom says I multiply straight across but just talking about right there 10.78 same thing all right before I write 10.78 there let's get to our scale drunk go back to our first page now go back to our first page alright what was our actual length the actual length of our classroom was 44 the actual width was 24.5 and then let's find our scale drawing so okay that's how we're going to finish this this is the most important part will do these later so so to find your new o g x a scale factor get your in 44 * 1/10 24.5 * 1/10 so this right here equals 44 / 10 this one right here equals 24.5 over 10 just like that last one we can move the decimal place over 4.4 this one right here we get 2 for 5 so let's look at a quick sketch and let's do a quick drawing let me see what is this p**** mature all right I got a few minutes just enough time I'll do these later will come Mac and find a new measurement does you need to know how but let's draw let's draw a rectangle so let's first look here are measurements from 44 feet. You 4.4 right there hold on all right so let's look at this right here look at my crappy remember the shape right here this is our sketch and we're actually going to do the actual shape of the classroom using this right here so I said we're going to use a ruler and let's use our ruler so let's do something wide enough but we can see Harry will use the light green so it is 2.45 what's measure this I'm not going to go all the way up here at centimeters so we could see so we got this here to here is one in here to here is to in here to hear is 2.5 that's too much we got to go a little bit back go one line back there's two .45 right there so let's measure that right there so on this right here and let you know and your homework is doing the same thing right here but you're going to be measuring your bedroom and give me all the details the floor plan here's to in here's to in and I got to go to .45 that's about right. Not quite a two and a half just before so there's two and a half how long are classes actually going to be but how that's how wide how long is 4.4 in jail right here here here is 123 + 4.4 is like two slime so it's just two lines below 2 and 1/2 let's line it up perfect like they're kind of off so notice right here we have the edge all I got to do like it's a rectangles match it up and if you go over that's all right cuz when you connect the dots that's all that matters to finish connecting to death so look at this right here this is the shape of the classroom I'm going to bring back our sketch in a second this is a good record this is how the classroom looks in real life but it's proportionally shrunken down it's a scale drawing how much gas to get my sketch look at house let's Jack. Never looked closer to a square then it is a rectangle look at this it's a lot more narrow slot more narrow than this so this is what you guys need to learn to do this is your homework so you're going to be doing a scale drawing so again let's look at this right here this is 4.4 and this is 2.45 let's look at length area equals area equals length times width 4.4 * 2.45 let's go this 2.45 * 44.4 plenty of time 2016 18 2018 and that's the same thing 089 no 0 0 is 0 8 9 there it is 08 17 Cara 110 I have three decimal places so 10.780 10.78 equals our area let's go back flip the page over let's go flip the page over look for us to have done and find the area that is for us to find the area we had the measure this through all that count all the squares but if we have the original air look at that right there 10.78 for our scale area can we change it to inches 10.78 square inches that's all right but notice we don't need to ask you have a drawing and find the new measurements to five area are we actually need to do is use the area factor in 10 him we're going to do more practice on this will let's find out an old measurements for Stuff let's go back to this right here so let's look at our windows are windows why would my steps though the sketch of the windows was six points it was cheers a thing we went length and width so this was the wish so when do needs to go on the whitside so 6.5 on wits and the door was on the width to the Whiteboard there's a whiteboard is here that's all so length whiteboard with a whiteboard 16 will stop there for now but let's calculate our new message I messed up our door wasn't 6.5 thank you for telling me it's 3 the job good catch I was lazy and I wasn't thinking so the door was three not 6.5 thank you thank you person who's paying attention siletz find our new measurements what are you supposed to do our original times are scale factor get to store new measurement so 6.5 * 1/10 here so this becomes 6.5 / 10 so for us to do the measurement right here let's move the decimal place over so here's the decimal place move it over becomes one we got to move it over right there so becomes .65 oops it's on the width I almost messed up .65 now let's look at this right here the door is 3 feet long so 3 ft three times the scale factor 1 equals 3 / 10 that's right 3/10 but that's three tenths so it's move the decimal 1 move the decimal over 1.3 so let's put the windows where they might go in the door where they might go .3 in what about the what about the end will end in 5 minutes or less if I let's finish our drawing couple done now so our door is a little bit over our door is .65 little more so here's what's a the door starts there she's a half an inch is right there so .6 5.75 is right here .65 let's use a different color that right there is R4 are window Mitsubishi 3000 I messed up I switched it so you kind of get the idea of pretty much finding your new measurements and putting them

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