Identify complementary, supplementary, vertical, adjacent and congruent angles

Vertical angles are angles formed opposite each other when two lines intersect.

Learn with an example

Look at  AEB and  CED:

CED and AEB are vertical angles.

Look at  AGB and  BGD:

BGD is adjacent to AGB.

Look at BGC and CGD:

 CGD is complementary to  BGC. Along with the right angle, they form a straight line. The straight line measures 180° and the right angle measures 90°. That leaves another 90°, so  BGC and  CGD have measures that add up to 90°.

let’s practice!