Question

In a parallelogram ABCD, ∠D= 115⁰, determine the measure of ∠A and ∠B.

Answer 1

Since the sum of any two consecutive angles of a parallelogram is 180

o

. Therefore,

∠A+∠D=180

o

and ∠A+∠B=180

o

Now, ∠A+∠D=180

o

∠A+115

o

=180

o

∠A=65

o

and, ∠A+∠B=180

o

65

o

+∠B=180

o

∠B=115

o

Thus, ∠A=65

o

and ∠B=115

o

.

Answer 2

Since the sum of any two consecutive angles of a parallelogram is 180⁰

Therefore,

∠A+∠D=180⁰and ∠A+∠B=180⁰

Now,

∠A+∠D=180⁰

∠A+115⁰ =180⁰

∠A=65⁰

And,

∠A+∠B=180⁰

65⁰ +∠B=180⁰

∠B=115⁰

Thus, ∠A=65⁰ and ∠B=115⁰