sat math question help

Test Preparation SAT Preparation
1

http://s3.postimg.org/b8dq5b2bn/2015_03_02_23_54_59.png

The answer is E but i don’t know how ?

Help is appreciated

2

Similar triangles. 16/8=(x+6)/10.

3

@Jr12317‌ thanks. i don’t how how didn’t that come to my mind.