Chapter 6, Problem 16SGR

To determine

The measure of angle ADC.

Answer to Problem 16SGR

  $\text{m}\angle ADC=65$

Explanation of Solution

Given:

The given figure is:

Calculation:

When a quadrilateral is a parallelogram, its consecutive angles are supplementary.

As angle A and angle D are consecutive angles, so they are supplementary.

So,

  $\begin{array}{l}\text{m}\angle A+\text{ m}\angle D=180\\ 115+\text{ m}\angle D=180\\ \text{m}\angle D=180-115\\ \text{m}\angle D=65\\ \text{m}\angle ADC=65\end{array}$