The sum of two intersecting internal angles at the intersection of two secant lines is 150 °. What are these angles equal to?

You need to know the signs (properties) of parallel lines, one of which says: “The internal angles lying crosswise are equal.” By the condition of the problem, exactly equal angles are given. If the sum of equal angles is 150 degrees, then this can be represented as the following equation y + y = 150. We decide: 2y = 150; y = 150/2; y = 75 degrees. These angles are 75 degrees.