Chapter 11.2, Problem 5GP

To determine

To find:The measure of $\angle 1$ .

Answer to Problem 5GP

  $\angle 1={30}^0$

Explanation of Solution

Given information:

  $\angle 4={150}^0$

From the given figure

We can say that

  $\angle 4$ and $\angle 1$ forms a straight line it means they are supplementary angles

So, sum of their measures is ${180}^0$

Using that

We get

  $\angle 1+\angle 4={180}^0$

On solving

  $\begin{array}{l}\angle 1+\angle 4={180}^0\\ \Rightarrow \angle 1+{150}^0={180}^0\\ \Rightarrow \angle 1={180}^0-{150}^0\\ \Rightarrow \angle 1={30}^0\end{array}$

Therefore,

  $\angle 1={30}^0$