Question

ABCD is a parallelogram in which ∠A = 110°. Find the measure of each of the angles ∠B, ∠C and ∠D.

Answer 1

Given ∠A = 110^o

But we know that sum of adjacent angles of a parallelogram is 180^o

∠A + ∠B = 180^o

110^o+ ∠B = 180^o

∠B = 180^o– 110^o= 70^o.

Also ∠B + ∠C = 180^o [Since ∠B and ∠C are adjacent angles]

70^o+ ∠C = 180^o

∠C = 180^o– 70^o= 110^o.

Now ∠C + ∠D = 180^o [Since ∠C and ∠D are adjacent angles]

110^o+ ∠D = 180^o

∠D = 180^o– 110^o= 70^o