Question

Please explain how you did it
[but if not thats fine too :)]

Answer 1

D. 3

Explanation:

The sides with lengths 25 and 5 are corresponding, so their ratio is 25/5 = 5/1

The sides with lengths 18 - x and x are also in a 5 to 1 ratio.

5/1 = (18 - x)/x

5x = 18 - x

6x = 18

x = 3

Answer: D. 3