Angle Relationships

Angle relationships refer to the ways in which angles interact with each other, including concepts such as complementary, supplementary, vertical, and adjacent angles.

Complementary angles are two angles whose measures add up to 90 degrees.

Supplementary angles are two angles whose measures add up to 180 degrees.

Vertical angles are the angles opposite each other when two lines intersect. They are always congruent (equal in measure).

The supplementary angle would measure 60° because 180° - 120° = 60°.

∠BOD would measure 56° because 180° - 124° = 56°.

Adjacent angles are two angles that share a common side and a common vertex but do not overlap.

To find the measure of an unknown angle in a linear pair, subtract the known angle from 180°.

The sum of the measures of angles in a triangle is always 180°.

When a transversal crosses parallel lines, it creates corresponding angles, alternate interior angles, and alternate exterior angles, which have specific relationships (e.g., corresponding angles are equal).