Answer:
[tex]\large\boxed{B)\ 256}[/tex]
Step-by-step explanation:
Look at the picture.
ΔABC and ΔBDC are similar (AA). Therfore the sides are in proportion:
[tex]\dfrac{AC}{CB}=\dfrac{CB}{DC}[/tex]
We have
AC = x + 144
CB = 240
DC = 144
Substitute:
[tex]\dfrac{x+144}{240}=\dfrac{240}{144}[/tex] cross multiply
[tex]144(x+144)=(240)(240)\qquad\text{divide both sides by 144}\\\\x+144=400\qquad\text{subtract 144 from both sides}\\\\x=256[/tex]
