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Math 7 - Module 1D - Lesson 16

Added Jan 05, 2021 •

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What is the Scale? Is it An Enlargement? or A Reduction?

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so if you look at this we eat in a lot of people said a lot of people went to this lot of people don't know what that is if you know what that is type it and I'll go with the second but this one right here it's a fingerprint if you look at it it's a big fingerprint and what's this right here a lot of people said it's too small to read correct there's a reason why I so you got to think what they're pretty much opposites of each other this right here is pretty much a bigger version of my fingerprint not mine but somebody's this is bigger this right here is smaller what is it I don't know yet it's always easy to see things that are better cuz it's second imagine you got a magnifying glass a microscope zoom in and what is the thing when you zoom in what happens to your picture gets bigger butt kindergarten first grade term so the term we are going to use for bigger is an enlargement all right Somerset should you write this down yes you should if you print it out right on your house right here you should so right here we got a bigger enlargement of the fingerprint bigger is pretty much an adjectives described but the noun is enlargement it's an enlargement tells you it's a man on this right here's a smaller of what one person has it one person that looks like the BART map but different true it's a subway map and here's the thing if you look really close zoom in and I can barely got these fuzzy fuzzy letters but they look weird you know it's it's Cyrillic I think is the term as they call it it's pretty much a subway map of a Russian city I think it's Rush looks Russian to me but yes will communist but I don't know where they chose but it's a map but it's a super small Matt is a bigger hands than me so we got smaller hands than me but we're using mine as a general size that right there the opposite of bigger is smaller the APA of an enlargement so let's see my vocabulary words is a reduction thank you reduction reduction the root word and reduction is reduce so we we we the root word in enlargement and large we enlarged it so what these are are based on something original we have a National we have an original picture We Shrunk down we have an enlargement when we have an original fingerprint we zoomed in on so there's always something called an original the original so scale drawings relating scale drawings to ratios and rates a scale drawing there's another word for scale drawing that's an image cuz you got to think in a thousand whenever you go if you ever visit your parents and they have access to a copy machine you stick your face in my coffee machine you put your face in this copy and Xerox it and then or you enlarge your face do you know if you haven't done and I know some of you guys has sat on the copy machine quotum code sat on it and you know I made a copy thanks I'm looking at some you guys are the laughing it's an image what the commission does it takes an image and the image can stay the same that's when it's a one-to-one so that's why if you looking pregnant does the symbol 121 it's a perfect copy same size and then you can shrink it down or you can enlarge it so the image is what's being shrunken so that this right here is an enlargement image this is a reduction image now there is a variable that talks about it he's right here have a number related to it we're not going to get to it today we will introduce it today we're not going to work with it today but I'm going to introduce it the scale is the variable r lower someone to talk about scale why is it little or lowercase I don't know reduction enlargement I don't know if there's 2 hours that I don't know what's why they chose our don't ask me but it's the lowercase r you got to think is this is a fingerprint list it's my fingerprint how many times bigger is it take a guess make a number how many times bigger this versus mine yes are equal scale correct is the variable for 6 x all right if I was a giant in The Incredible Hulk and then I got hit my gamma rays and I got angry and it turned my finger grew 6 times so someone said to really this is twice the size of my own 5 to be a good number someone said 10 5 to 10 is a good guess what so that's what we're going to do at the very last lesson of this module 1D we're going to figure out the exact number so we're going to have information and measurements and we will be able to figure out the exact enlargement so this right here notice what I'm going to say about all you guys is guesses none of them were small they were all bigger and there's one specific number this right here my finger is the original this is unit 1 all the numbers you guys chose were bigger than one so when it's an enlargement your scale are has to be bigger than the number one this picture is this this fingerprint image of my fingerprint is 5 times bigger than my regular is 6 times bigger than my original finger so it's always bigger than 1 what your original is always want you start out at 1 that's why I stopped at when he was real talk about unit rate we'll get to that tomorrow but when you reduce something you make it smaller a number has to be smaller so if my original this is I have some original picture and I it down that means it went happy greater than 1 and has to be less than 1 in this case are is less than 1 but but are has to be bigger if it's an enlargement you got to say the scale the scale of my picture is bigger than the scale of my fingerprint if I colored in my fingerprint you have an image of the enlargement of course the scale needs to be bigger you look at you go to the movie theater we love going to the movie theater cuz everything's bigger it looks bigger looks better on the big giant screen cuz the scale is so huge in a while what look at it a Transformer Optimus Prime doesn't look nice to me on my computer screen cuz he's like this small but if I watch Transformers in that movie theater Optimus Prime ginormous you could imagine what a giant robot looks like cuz you stand up the big short man that's why it has to be bigger than one it's zooming out the music bigger butter reduction if everything my originals based on one of the original the reduction shrinks it down so the scale needs to be smaller than one thing there's no such thing as a negative reduction in terms of a negative number OU shrank -2 times no we we cut something down if you look at a model no one builds models anymore at least I don't cuz they're expensive some you guys in your background you paid for those overpriced Gundam models man someone's rich or someone spoiled if you look at a model that's something to think of right now the scale of it is always a fraction so but a fraction has to be between one will not always cuz the guy was that fractions bigger than 1 but smaller fractions this last part right here is the key the scale on a reduction is between 0 and 1 so it's a fraction smaller than 1/4 tank model glad you guys got your remote control RC tanks that doesn't shoot anything just moves around look at the Box it'll say it's 1/48 scale that means that it is 48 times smaller than the original tank it shrank at 48 x 148 so scale reduction so those are the basic ideas let's go look at example one this stuff is super easy everyone should be able to turn in something today for credit and literally this is how easy this first example is oops for the following problems so I've got two problems got an A and A B for each of them a is the actual picture so look at that right there you got this little creepy haunted cursed pendant of an old Victorian lady and this right here we have a ruler I don't know which ones which but look at that so this is the original this is her actual ruler or measure and this actual picture so a is the actual picture B is the drawing or I mean use the word image cuz it's the copy and a copy can either be one less whole thing is the drawing is the copy an enlargement or a reduction of the actual picture so this right where is this an observation thing is just the reading vocabulary thing what happened to be did I enlarge it a reduce it and that literally tells you what is be that's the question is be the drawing is it an enlargement or reduction so on 1A here's the original now here's one be tell me type it in is it an enlargement or a reduction that at least let me know who's paying attention so be this right here where my pain is I want to draw a little mustache on her is it an enlargement or reduction you fool was just type that not you but long before you stop being funny correct correct good for 567 of you guys and type them in first person you just turn around I would like this it's an enlargement all right so the bigger so it's an enlargement in large e mint here's our original right here look at this right here let's zoom in on it actually so if you look at it why why did they choose measuring tape / ruler cuz look at it keeps all the parts 02102 2023 and it goes pretty much all the way to 10 and it cuts off on the same and look on the inside we got the little hash mark I'm saying these are little Parts / things are actually 10 little marks in here and there are 10 even smaller marks so everything gets reduced the same amount I gave the answer away so if you look at a you have the exact same image this is your image and it is literally exactly everything about it is shrunken down reduced the same amount so this is the reduction let's go Zoom back out and look at the creepy cursed pendant look at all the details got all these a little but say they were diamonds I'm assume it's a diamond and then killed an elephant for her ivory usually car that does your face I don't know that's why I made out of Jade or something and some some weird expensive stuff and then you know this old lady got Kirsten put herself in here and if you wear it you turn into her she takes over here but when I do it's a haunted movie everything is enlarged the same amount that's key that is very much keys are right here scale drawing A reduced or enlarged two-dimensional drawing of an original to pretty much an original so it's that's what it is a scale drawing it's an enlargement or reduction of something with a picture all right let's go next one yes it's only these Pages we can go through super quick so let's look at this right here now this was on our thing it says know how to actually comparisons Derek's family example to sorry Derek's family took a day trip to a modern public garden Derek looked at his map what is a reduction of the map located at the park entrance the dots represent the placement of rare plants the diagram below is the top view as Derek held as map while looking at hosted map so you got the best example I can save this for this example let's see you guys go to Great America or or Six Flags or if you're fancy go to Six Flags Magic Mountain or not Legoland Disneyland or even Fairyland does who doesn't like Fairyland I love Fairyland hater hater don't be talking smack about and just cuz you don't like puppets in the end there Italian ice, thing on there do you not like the d'Italia nice and a little slushy thing a man yes I love you have the key my sister stole my key to turn on the bus thank you though right and then you look on the call Summer posted in some section of the park to say where are you they always got a bigger math so here's whatever the math should be a huge I know who doesn't love it but show map should be way Huger if that's a way Huger I do that sounds funky and stupid but let's go with that but usually you get your souvenir map you're looking down on but notice facing the same way so this is a map you know if you got a Great America Six Flags this Lane whatever even real and they got that big giant wooden map like a poster of it so you stand and look at it correct yours is UPS so cuz the thing is why would the park have there's upside down so you're holding the souvenir math that give you and yours is upside down so I'll look at this good correct you could see it's upside down we have these that's why this is dark always look for something that you can identify in a picture that you could say okay which way is it turn this is upside down but sometimes just turned sideways one way or the other so right here we're looking at we'll get to that in a second and things are turned around smart thing to do is to redraw everything but which one do you want to redraw if you have two choices choose any of them I'm going to redraw this side facing the same way but I'm going to cover this up for now it always help you draw so what I'm going to do and notice my pictures not perfect but a picture is good enough for help to help you identify its why things are called sketches that's fine go ahead sketches help you identify it doesn't need to be super perfect but it helps you book in compare look at these pictures you could tell us upside down but when it's upside down you're zigzagging your head can't think straight you get cross-eyed it so first smart thing to do is just read run everything else is an Interstellar I got this line then it goes down about here then it goes across here then I got another line that goes kind of like this and then I got a circle connected to this and then about here I got this backwards and I goes all the way out here and then let's put some points on there but don't put those letters so that's all I'm doing is copying the picture I'm counting the points there's a point right there notice I'm not putting the letter on them just putting a point one seat and then there's one here and one on here no next thing I do I cover up the big one that's all I used it for was just the same now what I'm going to do is here's the thing on the copy the letters but look at this right here that's a and there's a point right here biggest mistake those of put in a right there cuz look right here hey is on top of this right here there's no point that's kind of on top right there cuz its flipped that's why you want to start out with the point that you can identify easily that's why this one is darker a comes first but start with y is he see why is right there so why has to be right here but notice why is on the left side why was on the right cuz it was flipped so if you look go straight down I hear you got where the two points meet where you least two lines meet that's H where these two lines meet that's h but you look which ones which a versus Mets two little two little lines two little lines towards the circle that's V two little lines towards a circle that's vv1 from the bottom now it's on the top and that means houses of elimination this has to be a next thing I do once done with my new picture I don't cross it out but I just kind of just in case I mess up my drawing I can always look back original I put a mark over it just cuz just having a visual cross out scratch it out you say okay I'm not looking at this anymore these two look at this right here are the corresponding points to the scale drawings of the map corresponding this is a geometry term corresponding means matching point corresponsal what point corresponds to point a a matches up with what on the other picture because that H matches up with what set with what and matches up with what corresponding means matching she have corresponding points and the only other thing you have is corresponding sides it so that when we do the geometry section in a south point A to point point a matches with Point are and notice points here's a thing they're always letters we always named points with letters Capital uppercase letters so if you write a lowercase that's like even though you got chores to write letter it's the wrong way of labeling it it's like when you write a letter dear mr. dear mrs. dear Ms dear doctor you always got to capitalize those titles it's just so it doesn't matter for that little half point so if you wrote point was it an egg was the point are you lose have a boy does R&L artist a little lower case hours of scale its capital r point B West Point Point V corresponds matches with that's noticed that's why you want to redraw the picture locate someone say man I could have saw that was supposed the pictures are so simple good I'm glad you noticed they're simple but when you get to a lot of the problems that you got a seizure always going to be more complicated with slaughter more sides lot of more numbers right now it's a simple way so we can see how easy it is to do making a sketch of your original facing the correct way to the other one is Eazy-E is 2W w h is to correct so H is 2p Point p mny is 2.10 redrawing we're rescheduling your original Too Faced the same way as the other one helps always identify it keeps you safe and it doesn't take that long to redraw something right now it's simple correct but what if you get something with a lot of styes a lot of lines a lot of points it's going to be easy to get confused so what do you uses for cellulite are wondering all this up when you get member you guys get the I ready diagnostic they actually use it and save your score and they present that to the Board of Education we're going to do the i-Ready diagnostic again when I don't know how to say I'll have they learned how they improved then why she gets the rain start here we're going to do the ren star test this month to see where you're at cuz you guys took the red star last or twice the rent star at least one maybe twice this year it's one of those other things that they use to send a way to like the city the state to say alright this is this student why is this due next haven't proved this much blah blah blah so these are questions these are yes easy questions yet these are easy questions but what if he had multiple points many more points easy to get mixed up so that's why you want to read right help right next one right here these looks like some stuff you guys did in first grade but look at this right here this is for you to do but we're going to talk strategy before you do it so exploratory challenge create a scale drawing of your own modern robots using the grids provided original good good someone's way ahead thank you next person said it even better the both of you guys thank you both of you people is the latest thank you ladies said the same thing but second person give you a little bit more credit but yes you you said it first below is a reduction to the side the right is an enlargement good you know where I'm going so you are going to make an exact enlargements right here you going to make an exact reduction right here but when it's when you're using a grid if you are making a scale drawing you want to make an exact spacing 2 count first so notice imagine this is an XY axis this is your starting point the origin 00 budget for the 102 that's 1/2 four five six seven eight nine 10 11 12 13 14 15 16 I'm 17 18 19 20 across what's double check to see if it's 20 price and everything from the original one here zero two three four five six seven eight nine 10 11 12 13 14 15 16 17 18 19 20 notice how much slower I had to go because my original smaller that's why we love enlarging things cuz we can it's better to do work when it's in large but things always look more detailed and prettier when there shrunken down you know you got to think if you do a giant origami crane let's funky looks like a pterodactyl when you shrink a folder what's better same thing so here's your original trying but because it's smaller it's harder to write out the details skip this prison Florida but now I go here 01235 six seven eight nine 10 11 12 13 14 15 16 17 18 19 20 I got to go super small and lot more detail because it's less space to work with we always like to we always want to shrink things down cuz it's going to feel cuter but it's hard to do the word because more detailed and it's cramped so we can see that they're all 20 spaces apart but the spaces from my original to this one other bigger why are easy to work with smaller butt still 20 spaces apart let's count to see how tall it is the matchup and I'm doing this first and you guys should be doing this to cuz it makes it easier to find where all the point. We'll get to that in a second let's count first one two three four five one two three four five one two three four five one two three four five 1 2 3 4 5 by Wiz so how long 20 by 25 it's go with that X-Men why so same thing right here we should do the same things right here and count it cuz it'll make it easier for me to match up so let's go with this one to see I messed up 145 1 2 3 4 5 1 2 3 4 1 2 3 4 1 2345 so now I have a grid that little extra bit right there helps cuz nice identify your points and graphing do the same thing you did it on your own but notice right here when I'm going to next on every corner I'm going to put a point because I have a grid system all I have to do is match of the grid system could have helped connect the dots so timer I'd give you enough hints they should be able to do this on your own I'm going to give you 5 minutes if you take more than 5 minutes to count numbers and connect dots man back to preschool and buy you can connect the dots book no I'm lying I'm not going to buy Connect the Dots book I can't even afford that right now myself yeah Trevor Noah make an enlargement and make a reduction and after this yes we got one more page after this just thank you for letting me know already told you that person does that man this is easy this chapter was a section this lesson is and this is an introduction for everyone to do we are ahead of time while you're drawing cuz you can talk at the same time as anybody been to the Shake Shack downtown Oakland going to try the burger but I don't want to waste money if it's overrated a stick with a net in and out in and out in Southern California I'll try then we had a which was the other one the habit and then we had Chick-fil-A but that's only chicken but not run with Chick-fil-A but there was a fancy burger place that was in I think Central Park New York it was literally called The Shake Shack it was a Shack in the middle of the park what are the fancy Shack so supposedly they're their milkshakes are really awesome their burgers are pretty good I heard their fries Army but they opened up a bunch of Shake Shack's here in the bay in the freaking expensive cities San Jose Palo Alto I forgot where else oh over the Marin County and they open one in Downtown Oakland where the Uber building used to be stop the front door. I guess I won't get there shakes just want to see who had it and plus I signed up under stupid mailings to send me a coupon good done excellent I got a couple things done if you're done I'm going to wait another minute or to give up with a chance and then some of you guys are staring at your other school watching your Netflix show you should be doing this as a reason why I don't come to me and say what can I do to pass if you can't do the something this simple thank you let me know and if you're watching something a couple suggestions I got then I watched during break I binge to chose Alice in Borderland which is based on a video game I think a PlayStation 4 game bicycle made an enemy of it but I think it if someone told me and was based on a comic book 2 it was almost like a weird Hunger Games connect the dots yes do that and then I watched a wannabe Mortimer video game in Zombie but it felt like a like a Resident Evil types of video games suggested sweet home so I binge watch that more like monster zombies mutations on this show Mentor read 4 books I did on my Christmas break yes for books I know I didn't do nothing I wonder where am I going to go I can't go anywhere so I decided to watch a bunch of shows finished all my Mandalorian binge watch two shows watched a bunch of movies I never watched and then read a bunch of books it's all right as long as you know you kind of get the ID on the grid books I read if you guys watch that move Ready Player one that was based on a book so I read the book first I want to watch the movie but then the guy wrote a second book of Ready Player two so I read that then I went and if you guys know there's a movie called The Notebook with Ryan Gosling that that was based on a book to but then that author Nicholas Sparks write brought a ton so I read his book The return then I went and wrote read the the Harry Potter author JK Rowling other book bag and then I read the prequel to The Hunger Games it tells you why President Snow is the way President Snow is I think they're pregnant do a second prequel book cuz they left it kind of hanging he just became a military person after that I read those four books and I started a fifth one and I started a bunch of them that I didn't finish the Harry Potter awesome I want to speak with an English accent I want to say happy Christmas instead of Merry Christmas but the British people in Hogwarts happy Christmas Ron happy Christmas and whatever that's why I gave you the hint to put numbers on here grids so pretty much as I live you guys are going to learn this that if you guys are going to go for that extra thing in your village I see that's all they can do it when you guys do your military outings little outings with the with that whichever can you work with to take you somewhere and use the map to coordinate at Camp Parks there it is you know you're always going to use your compass but you got to figure out your longitude and latitude longitude left to right in latitudes up and down. you're going to look at the grid see look at this right here I go up one square but this right here he was five and then I go to over so the numbers are the same it's just the bigger so I'm up then I go over from 5 to more there's my first one that I go look at this instead of starting over I use this is my next I go 3/3 / then I go 3 over again look at that the feet how high do I go I do not know yet so right here I'm going to go straight up I know there's a point straight up straight up and straight up so what is this right here so that's 10 that's my 10 Mark I go down 1 so 10 no time to care about this I'm going to use this cuz look at this right here it's straight up it's a marker 10 and I'm going to this one will show you why in a second so one under the tents that's a nice go over to this Mark so 110 and I go over and I'm right above this look at this cuz it's supposed to be a straight line all I got to do is just copy it right there repeat it and now look at this right I got one Mark over a point that's over one or back one Ford one and then look at this I go up one of one from there and then I go out who to go to my fingers out to too and now I got to start again but look at this from this point right here all I got to do is line up so I know I'm going to have a point somewhere on this line and I got another Point summer on this line to make my shoulders so let's go look at this this right here is a fair but what is that right there that's 20 is this right here is 20 then what 19 and went down to 18 so I find might want to go to 18th and I just line it up with these here I here and then look I go across in the one I got one right here I go over 1 and then up for over 1 and then up for and then I go for over to make the top of my head and then I know I got to go down and over 1 and then another one I have all my points and all I got to do now is connect the dots the same way then connect the Deez so let's do the legs first and noticed I didn't do it perfect so I'm not like a robot I can't do straight lines all that great because it's bigger cenotes I kind of came out that's okay it's okay and then I just go right here cuz this is my little oversized sweater and then they don't connect the straight line that just connect right here here my hands and here's the rest of Jackie right here and then here in my arms it's not perfect but it's good enough and then my shoulders and then I got to go across the finish my shirt and then my head is a weird shape now you have an enlargement that's why it's important to know how to make a grid system know how to use your your your ex y-axis now right here I'm going to try and do a quick as I can but did this one this right here is a little bit hard because it's less space reductions aren't as easy so you got to be careful but let me first finish timing this right here 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 right even though I know that's 25 you always want to finish counting just to make sure you didn't skip numbers and mess up so again I go up one then over to 7 why is height correct so this is your ex Acts this is your why axis so I want to look for this point right here so then I go over this 7 here's 567 and I just go up one and I don't need to start over cuz I know to make an image you want to follow the exact staff that's what I'm doing I go 3/3 / gets me to hear that's my other leg and I go three over then I got both of my legs and I'm supposed to go up straight up to complete my leg my pants right here in Hurst 10 remember down one so it's 9 so here's ten I go down that's in line and I just want to line it up right there right there right there and then I got to the one over to complete my t-shirts and then I go up one because that's where my hands start and then I go over to notice I'm slower but all I'm doing fall I I I didn't want you to bring that up so much like you hated my Harry Potter other person I hate your Minecraft it annoys me but yes I get it like Minecraft it's just this Legos in Minecraft just digital Legos real Legos but yes it's yet more less what you're doing you might meet but notice if you're replicating something you it's match the blocks you can shrink the block make it bigger but noticed yeah... The more blocks you put in it and then you should not mad it looks really awesome but when you get salt block and chop detail so right here what am I supposed to go to 18 18 and over that so there's 20 and then here's a teen and I go over then I want to match up and then I go 1 in then I go over 1 and up for 1 2 3 4 on the floor two dots we'll connect the dots the way they should be connected I noticed even though I messed up right here when you messed up on a reduction it doesn't look as bad as an enlargement cuz it's details so much smaller so that's why people like reductions took me longer to do even though it was smaller space cuz it's all cramped up but as not perfect looks so much better reduction it's easier to hide your mistakes when you're crammed everything together but it's quicker to do that it's another metaphor of mass who carries a ton of space on a paper show your work it doesn't need to look perfect the calculations need to be perfect a reduction man look how much harder to do when you cram things in it's a metaphor all right let's go so easy to reduction so you need to know how to make a reduction and at the same time you're not going to be asked to do this on a test what do do though is the Highlight unoriginal points and then they'll give you a new grid and do choose different numbers or lettering system so they'll choose a different system they won't use numbers so on your original probably use a number and on your second test question the price use letters and those all right here at this point right here a at 71 what point does it match with on the reduction where were where would it be on your reductions scale and they'll have letters here in a point I don't know what's the seventh letter a something a a b c d e f g g g a to draw grid the Pulaski Define where would be where would it be on this matching grid you know all right almost done almost done so this is right here's the introduction to the numbers so let's look at this right here Celeste Drew and outline of a holding for a diagram she was making an injury second mimicking mimicking is pretty much just making a copy mimicking is copying Double Check Yes I write it right so she drew a second copy her original drawing State the coordinates of the vertices and fill in the table all right so this right here you got to know how to look at the coordinates so right here this is where she made something slightly different you look at this right here that right there is seven zero this right here is all right so that's 10 that's 15 while it's count backward 15 14 13 imma get this right here she started at 7 still the first one didn't move seven zero but this right here that's 10 0 so what's the difference the difference compared to where did I get this great look so think about it I'm kind of by 0 5 10 15 20 but when you grasp it's not always nice and perfect when they put it on top of the number sometimes it's in between so if you zoom in let me zoom in and you can't really see this is a good question. Thank you for asking little fuzzies pink lines right there those are all the other numbers so pretty much even though there's no one the number one is not written you can see is funny Fantasy 1 2 3 4 5 I go bowl 6 7 is where that is 8 9 10 season 10 so why are the numbers different computer look at this though let me go bring back the other picture on this one right here but I understand back out now we actually Shrunk the grid squares look there's my original the reduction the grid squares are smaller in the the grid squares are bigger so we want to match for the grid marks are but this right here's a different from where the grid doesn't even shrink your using the same grid what you actually shrank the sketch this is what we're going to get into the court harder stuff but it's not hard we're actually going to see did we shrink it correctly or was a shrunken correctly so here's 70130 now discount this right here we know that 7:00 on the X we go all the way so here's 20 and here's fifteen so we know that Mark is between 20 and 15 so if this top-line is 22 below that makes it 18 the distance 718 and this right here is 13 cuz he went over 13 and how high is it that's 18 so 13 18 yes number lines correct perfect so now we did the small and it was with a smaller one we went over to seven and notice here's ten this Mark is my timeline this is just below so it's one below that's 9 high so I go over to 7 and then I go up to 9 so this is seven nine perfect you're correct and then with this one right here we know it's 9 high but we went over ten spaces over ten of tonight remember all coordinates all coordinates have the form you go your ex then why you find your ex number and then you go up to how high it is so my ex number was set but I don't go anywhere that's why I 0 and then I zoom up its 9 high on this one I go over to the 10 and how high does it go 9 10 nine so looking at this look at her numbers the original drawing how high is it only this what's great about numbers that start at 0 we can always count E-Z-Go 0 all the way up to 18 why is how high it is so the height of my original is 18 let's look at how long it is the cheers this though this didn't start on zero we shifted it over we started at 7 so you can look at it how long is it from here to hear you can count steps 123 4566 steps so you can start from here and count how many little box units to go in at 6 but another way to do it look at this based on these numbers this is called the distance formula if you don't start in the 40 where's my ruler where's my ruler usually let me measure things most of us are smart enough to start to line in line up 2018 if we don't line it up and we start measuring from somewhere else we landed from here and it ends so you can she find the length distance of anything by subtracting the numbers you don't want a negative but if you get the negative just throw away the negative side 13 - 7 equals 6/6 units long let's look at this right here you can easily how many steps do you go from set step 7 to step 10 that's three you can see there's three boxes in between there what's 10 - 7 three so that's our length all right already filled it in my original length is 6 my second length is 3 now let's go look at my second height I went from down here I started a jar how high does it go 9 this is what we're going to get into so we're introducing it today because this all right so we filled it in succubus here's my original height here's my my my image height I went from 18 to 9 here's my original length 6 here's my image like three can someone tell me look at this is this a reduction or an enlargement is my original there's mine so sometimes they'll just give you the number so we're giving you both triangle is it it is this a reduction or an enlargement thank you three people yes it's a reduction reduction get smaller look at the numbers here's our original drawing 18 and Game Night. Smaller ears original 463 got smaller so it's a reduction excellent we're almost done so we can see it's a reduction reduction got smaller you can see by based on the numbers I got smaller but how much smaller so if you say you shrank something you know let's say let's say you had 12 donuts from donut Savant over there by Mikasa delicious Lucy got some donuts from donut Savant you by the Dozen before you got home when you got home you said hey everybody I got six donuts from donut survive for you guys that means u86 yourself what's that what's the reduction so you don't say one way you said it got reduced by 6 but if you had a dozen and there's six left how much did it get reduced by how would you describe instead of using the word out six less you started with 12 and then you had 6 cast reduction is based on a fraction good job so it's six less which is true 6 x 6 less but when you reduce something you went from 12 to 6 you reduced it by half so look at this right here I went from 18 to 9 almost done work from 6 to 3 we were you stood by half look at this it's always new over original that's always what you want to make a fraction out of when you're doing this so my new number is 9 my original members 18 my new number is three my original number is six look at both of these they both get reduced be simplified to one half if they're both the same it's a perfect reduction you call it an exact reproduction this right here we're going to do super quick look at this 02028 so here's a date that mean my my original how wide is it its 3 how tall is it 025 that's 5 look at this right here my with I go from 5 to 15 that means it and long and then I from 50 all the way up to 15 that means it's 15 High original new over original sorry I sorry I did that right there so many scoot over so we went from 5 to 8 spaces that's three units wide that's my original and then right here you could c025 it's five units tall that's why it's 5:00 and on my second image I go from 5 to 5 that means I move ten spaces ten spaces why how tall is it I start from down here I go all the way up to 15 that's where that is let's compare Sony you over original my height 18 / 5 that's 15 / 5 which is 3 look at this my new versus original 10/3 you can easily see that this is not a 15 / 5 310 / 3 is not 3 so they're not equal not a perfect it's not it's not an exact it's not a reduction Debbie it's not or enlargement thank you it's enlarged but is it a perfect enlargement no because they don't match up and we're going to go over that tomorrow not tomorrow the next lesson so we'll answer these questions later but you can pretty much try and answer it yourself the problem set is on the module yes we're going to go over that but you can see that they don't match up when they match up it's a reduction / enlargement but this even though the numbers got bigger new picture is off that's why we can't call it an enlargement that's the basic idea will go over that but the homework is super easy please do it and start your new semester on a perfect thing I have nothing else for you yes you may leave now see you later bye bye

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Math 7 - Module 1D - Lesson 16

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