In parallelogram ABCD, angle B is 40 degrees greater than angle A. Find angle D-?

A parallelogram is a quadrangle in which opposite sides are parallel and equal to each other.

Since the sum of the angles of the parallelogram adjacent to one side is equal to 180º, and the angle ∠B is 40º greater than the angle ∠A, then we express:

x is the degree measure of the angle ∠A;

x + 40 – degree measure of angle ∠В;

x + x + 40 = 180;

2x = 180 – 40;

2x = 140;

x = 140/2 = 70;

∠А = 70º;

∠В = 70º + 40º = 110º.

Since opposite angles in parallelogram 6e are equal, then:

∠А = ∠С = 70º;

∠В = ∠Д = 110º.

Answer: the degree measure of the angle ∠Д is equal to 110º.