Parallel lines are crossed by a secant. The one-sided angle difference is 40 degrees. What are these angles equal to?

Let’s solve this problem using the equation.

Let one of the one-sided angles be x degrees, then the second of the one-sided angles is (x + 40) degrees. We know that the sum of the degree measures of one-sided angles is 180 degrees. Let’s make the equation:

x + x + 40 = 180;
x + x = 180 – 40;
x + x = 140;
x * (1 + 1) = 140;
x * 2 = 140 (in order to find an unknown factor, you need to divide the product by a known factor);
x = 140: 2;
x = 75 degrees – one of the one-sided corners;
75 + 40 = 115 degrees is the second of the one-sided corners.

Answer: 75 and 115 degrees.