Chapter 2.1, Problem 12PSB

To determine

To calculate: To find measure of $\angle PEF$

Answer to Problem 12PSB

  ${15}^{\circ }$

Explanation of Solution

Given information: $DE\perp EF,\angle PEF,\angle MEN,\angle NEF$ are equal. PE Bisects $\angle NEF$ , according to given conditions.

Calculation:

First draw the figure according to the given condition

  

Now.

  $\begin{array}{l}\angle DEF={90}^{\circ }\\ \therefore 3\angle NEF={90}^{\circ }\\ \therefore 3\times 2\angle PEF={90}^{\circ }\\ \therefore \angle PEF={15}^{\circ }\end{array}$