Introduction to Geometry: Rays and Angles

Congruent Angles

When two angles have the same measure, we say that they are congruent. Congruent means having the same size and shape. When we look at angles, remember that we are only concerned with how wide the opening is. We may draw the rays longer or shorter, but the angles are still congruent.

angle R S T with measure of 85 degrees angle X Y Z with measure of 85 degrees

Angles RST and XYZ are congruent because they have the same measure. We use the symbol
" congruent symbol " to show that two figures are congruent.

angle R T S is congruent to andlge X Y Z is read "Angle RST is congruent to Angle XYZ."