Chapter 16, Problem 4RP

To determine

To find: The value of DF.

Answer to Problem 4RP

The value of DF is $9.508\text{unit}$ .

Explanation of Solution

Given information:

The given figure is,

  

The value of DFis calculated as by using Stewart’s theorem,

  $\begin{array}{l}{7}^2+8^2=\frac{5}{9}{\left(\frac{3}{2}DF\right)}^2\\ {\left(\frac{3}{2}DF\right)}^2=\frac{1017}{5}\\ DF=9.508\text{unit}\end{array}$

Thus, the value of DF is $9.508\text{unit}$ .