Which type of angles are equal to each other?

Opposite angles are the angles that are formed when two lines intersect. When two lines cross each other, they create four angles, and the angles directly across from each other are called opposite angles. These opposite angles are equal in measurement because they both share the same space, with their vertex located at the intersection point of the lines. This property stems from the fact that they essentially represent the same angle from different perspectives in a geometric sense.

Complementary angles refer to two angles whose measures add up to 90 degrees, but they are not necessarily equal. Adjacent angles share a common side and vertex but may differ in measurement, and straight angles refer to an angle of 180 degrees, which is not a comparison of two different angles but rather a single angle measurement. Thus, while these other type angles have specific properties, it’s the opposite angles that are always equal to each other.