In a trapezoid, the two angles that are on the same leg are called adjacent angles. These adjacent angles are supplementary, which means their measures sum up to 180°
Therefore, we can conclude:
[tex]\begin{gathered} m\angle C=180-m\angle A=180-122=52 \\ so: \\ m\angle B+m\angle C=180 \\ m\angle B=180-52 \\ m\angle B=122 \end{gathered}[/tex]
Answer:
a. 122
