Question

Triangle SDF is similar to triangle RTY with ratio of similitude of 4:9 . Also, SF is 2 less than RT and TY is 9 more than RY. IF SD = 8, what is DF?

Answer 1

@Loser66

Answer 2

I thought we solved it yesterday, right? Not exactly the same, but the same topic

Answer 3

Yeah we did... But I don't know how to set up the equation..

Answer 4

look at it and let me know if you get why I label them like that. I will guide you more

Answer 5

Ok.. I understand

Answer 6

The ratio is \(\dfrac{SDF}{RTY}=\dfrac{4}{9}\), that is \(9SDF= 4RTY\) ok?

Answer 7

Alrighty

Answer 8

Now, for a: we have 9*8 = 4 *a (from the ratio), hence a =??

Answer 9

don't get ???

Answer 10

Yeah i get it

Answer 11

now what

Answer 12

a=??

Answer 13

18

Answer 14

then a-2 =?

Answer 15

16

Answer 16

ok, now again, a-2 is from the small triangle, and we know that the ratio is 4/9 , that is 9 small = 4 big
the associate side of a-2 (from small one) is b (from big one) hence again, 9small = 4 big
that is 9(a-2) = 4b, we know that a-2 =16, hence b =???