Question:
ABCD is a parallelogram in which ∠A = 700. Compute ∠B, ∠C and ∠D.
Solution:
In a parallelogram ABCD
∠A = 70°
∠A + ∠B = 180° [Since, adjacent angles are supplementary]
70° + ∠B = 180° [∵ ∠A = 70°]
∠B = 1800 − 70°
∠B = 110°
In a parallelogram opposite sides are equal.
∠A = ∠C = 70°
∠B = ∠D = 110°