Question

In the accompanying diagram of parallelogram ABCD, angle A =2x-10 and angle B =5x+15. Find x.

Answer 1

x = 25

Explanation:

Mathematically, one of the properties of a parallelogram is that consecutive angles of a parallelogram are supplementary

What this means is that they add up to be 180

A and B are supplementary, and this means that their addition equals 180

Thus, adding A and B equals 180

2x -10 + 5x + 15 = 180

7x + 5= 180

7x = 180-5

7x = 175

x = 175/7

x = 25