Respuesta :

Answer:

15

Step-by-step explanation:

because the sides 15, 25 are corresponding, sides 18, 30 are corresponding, 9 and x (unknown side) are corresponding.  here we discover that the ratio is 3:5 (15:25) and (18:30). so if the ratio of 9 to x is 3:5, the unknown side is 15.