Question

in the figure below, b is between a and c, and c is between b and d. if bc = 7, ac = 11, and bd = 12, find ad.

Explanation:

Step1: Find length of AB

Since $AC = AB + BC$ and $AC = 11$, $BC = 7$, then $AB=AC - BC$. So $AB = 11 - 7=4$.

Step2: Calculate AD

Since $AD=AB + BD$, and $AB = 4$, $BD = 12$, then $AD=4 + 12$.

Answer:

$16$