Angles

Front

Less than 90° angle

Back

ACUTE

Front

Exactly 90° angle

Back

RIGHT

Front

Between 90° and 180° angle

Back

OBTUSE

Front

Exactly 180° angle

Back

STRAIGHT

Front

More than 180° angle

Back

REFLEX

Front

Angle that measures 360°

Back

FULL CIRCLE

Front

Sum of angles in a triangle

Back

180°

Front

Complementary angles

Back

Two angles that add up to 90°

Front

Supplementary angles

Back

Two angles that add up to 180°

Front

Vertical angles

Back

Angles opposite each other when two lines intersect, they are equal.