One of the adjacent angles is 20 degrees smaller than the other. Find the smaller of these angles.

It is known from the condition that one of the adjacent angles is 20 ° less than the other. And we need to find the smaller of these angles. To do this, we will compose and solve a linear equation.

For this we apply the theorem on the sum of adjacent angles, which says that the sum of adjacent angles is 180 °.

Let’s denote by x degrees the larger of the adjacent angles, then the degree measure of the smaller angle is (x – 20) °.

We get the equation:

x + (x – 20) = 180;

x + x – 20 = 180;

2x = 180 + 20;

2x = 200;

x = 100 ° larger angle and 100 – 20 = 80 ° smaller angle.