If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
Current time:0:00Total duration:2:55

Corresponding points and sides of scaled shapes

CCSS.Math:

Video transcript

we are told figure 2 is a scaled copy of figure 1 so this is figure 2 here this is figure 1 looks like figure 2 not only has it been scaled down it's a smaller version but it also looks like it has been rotated 180 degrees or you could say it's been flipped upside down we're asked to identify the side in Figure 2 that corresponds to side ei in Figure 1 so this is ei in Figure 1 pause this video and see if you can identify the side of Figure 2 that corresponds to side ei in figure 1 alright now let's work through this together some of you might immediately into it or be able to spot which side corresponds to ei but I'll do it slightly more methodically in this video just so that we can see maybe all of the corresponding sides and points so one way to think about it is well it looks like the longest side in Figure 1 is side BC so this is the longest side in Figure 1 and then the longest side in Figure 2 is HL so it looks like BC corresponds to HL and then touching on that longest side that longest side has two right angles it forms two right angles with the sides next to it so you have these two right angles right over here and then of those two right angles you have the sort the shorter side connected to the longest side and so that is VA over here and so that would correspond to LK right over here that is the shorter side connected to the longest side that forms a right angle and then if we just keep following that side of the shape we then go to side AE which would correspond now - and this is answering our question - side K J so the the side in figure 2 that corresponds to EA in figure 1 that is going to be K J or we could say side j k and if someone wanted to say what points correspond to which point well you can see that B a corresponds to L K and B C corresponds to L H so we would know for example that this point B right over here point B would correspond to point L in figure 2 right over here and we could use a similar logic for the other points so we've answered the questions the question but the real thing is to see well which which sides or points have similar features on a relative basis so I said what is the longest side what is the longest side where do we see right angles and sometimes your brain might just immediately be able to spot out the shape if you were to rotate this one all the way around it would jump out at you a little bit faster that JK and a e are corresponding sides