Similar figures have corresponding sides that are proportional.
We can set up a ratio where we are putting corresponding sides of each triangle, cross mutliply, and solve for the unknow.
Looking at answer choices:
A)
if we have x and 24 to one side, we need corresponding pair from right hand side triangle, which should be 15 and 9. But the ratio is 9 over 15. So, this isn't right.
B)
If 24 is paired with 9 [corresponding side of each triangle], then we need same correspondence.
But we have 15 and x, which is opposite of what we want. So, this isn't right.
C)
32 goes with x and 12 goes with 15. They are indeed in correspondence to each other.
This ratio is correct.
We can say Option C is the correct answwer.