Answer:
Explanation:
Opposite angles of the parallelogram are congruent:
- 10x - 19 = 7x + 23
- 10x - 7x = 23 + 19
- 3x = 42
- x = 14
Find the angle B:
Adjacent angles of the parallelogram are supplementary:
- m∠B + m∠C = 180°
- 121° + m∠C = 180°
- m∠C = 180° - 121°
- m∠C = 59°