Question

The polygons are similar, but not necessarily drawn to scale. Find the value of x.

Answer 1

The two known numbers of "similar" sides tell you how much bigger the poly on the right is. Use that ratio (bigger over smaller) to "scale" (I mean multiply) 5 into a bigger number representing the length of unknown side x.

Answer 2

so would it be 195?

Answer 3

Lengths of corresponding sides of similar polygons are in proportion.

AD is to JM as DC is to ML

Algebraically, that is written as AD/JM = DC/ML

From the diagram lengths,

20 is to 39 as 5 is to x

20/39 = 5/x

Your turn:

Cross Multiply and solve for x.

Answer 4

20/195?

Answer 5

try again?

Answer 6

Think like this. the poly on the right is 39/20= 1.95 bigger, almost two times so the answer would be about twice the similar length on the left poly that being 5. So the answer is near?? and is precisely?

Answer 7

so you were close you had 195 which should have been 1.95. Yes that is how many times bigger the right poly is the left.

Answer 8

umm so you moved the decimal once you got the answer?

Answer 9

no 39/20 is indeed 1.95

Answer 10

but i don't see that as answer i see 195,156,9.75.11.8

Answer 11

maybe printing mistake

Answer 12

yup cause you are not done.

Answer 13

you know know how many times bigger, so the side of interst X corresponds to 5 in the left poly. So you need to scale 5 by 1.95 to get the answer x

Answer 14

um im not done so what do i have to do? and i doubt it's a printing mistake lol

Answer 15

by scale you mean multiply?

Answer 16

Yes! that's what it means to scale.

Answer 17

oh okay so i got 9.75 is that correct?

Answer 18

From above:

20/39 = 5/x

20x = 39*5

4x = 39

So, x = ?

Answer 19

Yes! excellent. My approach is a bit more intuitive. you should review my method vs AvravindG's both work.

Answer 20

oh okay thank you sooo much :)!!