Chapter 3.5, Problem 12PPS

To determine

To state the postulate or theorem justify the answer.

  $m\angle 3+m\angle 6={180}^{°}$

Answer to Problem 12PPS

Theorem of co-interior angles is used.

Explanation of Solution

Given information:

Figure

  $m\angle 3+m\angle 6={180}^{°}$

Figure

Co-interior angles

When two parallel lines are cut by a transversal and sum of interior angle is ${180}^{°}$ .

In figure $\angle 3$ is on the line u and transversal s and $\angle 6$ is on the line v and transversal s are

Co-interior angles.

In figure parallel lines are

  $u\left|\right|v$

Then

  $m\angle 3+m\angle 6={180}^{°}$

Hence, $m\angle 3+m\angle 6={180}^{°}$ are co-interior angles.