Parallel Lines cut by Transversals

The value of x is 180, because the labeled angles in each diagram are supplementary.

The value of x is 90, because the labeled angles in each diagram are complementary.

The value of x is 44, because the sum of the measures of the labeled angles in each diagram is 180 degrees.

The value of x is 136, because the labeled angles in each diagram are congruent.

$$\angle5\ and\ \angle8\ are\ vertical\ angles$$  

$$\angle3\ and\ \angle5\ are\ congruent\ angles$$  

$$\angle1\ and\ \angle8\ are\ alternate\ interior\ angles$$  

$$\angle2\ and\ \angle8\ are\ corresponding\ angles$$  

$$\angle1\ and\ \angle7\ are\ \sup plementary\ angles$$  

$$\angle8\$$