Question

What is the length of DE?

Answer 1

The length of DE is 5 because they are similar triangle .

Answer 2

Answer: B. 6

Step-by-step explanation:

The triangles are similar. We can use the SAS similarity theorem to prove that claim.

Because the triangles are similar, the corresponding sides form a proportion like shown below

12/8 = 9/x

12x = 8*9 ... cross multiply

12x = 72

x = 72/12

x = 6 which is why the answer is choice B