#2**+3 **

Since the triangles are similar, that means the ratio between each of the sides will be same.

You can find that the ratio between sides is 2:7 (by comparing AB to XY and BC to YZ).

Since we're tryna find N, you need to divide AC by two (to get 1.5) then multiply by 7.

The answer is **10.5**

uvacowdo Aug 7, 2020