Answer:
79°
Explanation:
The angles created by a transversal line and 2 parallel lines have special geometric properties.
Transversal Lines
A transversal line is a line that intersects 2 lines. In this case, the vertical line is the transversal line, and it intersects lines a and b. Additionally, the question states that a and b are parallel. The angles formed by parallel lines intersected by a transversal have unique relationships. These relationships can help prove either that angles are congruent or supplementary.
Alternate Side Angles
One relationship between specific angles is called alternate side angles. Alternate side angles are angles that are on the opposite side of the transversal. For example, angle z is on the left and angle x is on the right. These angles are alternate side angles. However, it's important to note that alternate side angles are not adjacent. This means that angles b and x are not alternate side angles.
By this definition, angle b and the angle of 79° are alternate side angles. Alternate side angles are always congruent. Thus, angle b = 79°.