Question

in the figure below, b is between a and c, and c is between b and d. if ad = 11, bc = 5, and bd = 7, find ac.
ac =

Explanation:

Step1: Find AB length

Since $AD = AB+BD$ and $AD = 11$, $BD = 7$, then $AB=AD - BD$. So $AB=11 - 7=4$.

Step2: Calculate AC length

Since $AC=AB + BC$ and $AB = 4$, $BC = 5$, then $AC=4 + 5=9$.

Answer:

9