Question

What are the steps to solving this problem?​

Answer 1

Answer:

$\large\boxed{B)\ 256}$

Step-by-step explanation:

Look at the picture.

ΔABC and ΔBDC are similar (AA). Therfore the sides are in proportion:

$\dfrac{AC}{CB}=\dfrac{CB}{DC}$

We have

AC = x + 144

CB = 240

DC = 144

Substitute:

$\dfrac{x+144}{240}=\dfrac{240}{144}$    cross multiply

$144(x+144)=(240)(240)\qquad\text{divide both sides by 144}\\\\x+144=400\qquad\text{subtract 144 from both sides}\\\\x=256$