Respuesta :

Answer:

The correct answer is B. y = 5

Step-by-step explanation:

Let's recall that two are triangles are similar when its side lengths are proportional. That is in our case, if Δ ABC is similar to Δ DEF , then the following equation holds:  

EF/BC = DF/AC

Replacing with the real values:

6/12 = y/10

Cross multiplication:

12 * y = 10 * 6

12y = 60

y = 60/12

y = 5

The correct answer is B. y = 5