501 Geometry Questions

Complementary Angles

When two adjacent or nonadjacent angles have a total measurement of 90°
they are complementary angles.
You can probably see that these are similar to supplementary angles,
except complementary angles add to 90° instead of to 180°. The following
two illustrations show examples of adjacent complementary anglesand
non-adjacent complementary angles.

m∠ROQ + m∠QOP = 90° m∠OTS + m∠TSO = 90°
∠ROQ and ∠QOP are ∠OTS and ∠TSO are
adjacent complementary angles nonadjacent complementary
angles

Supplementary Angles

When two adjacent or nonadjacent angles have a total measure of 180° they
are supplementary angles.

m∠MOL + m∠LON = 180° m∠XUV + m∠UVW = 180°
∠MOL and ∠LON are ∠XUV and ∠UVW are non-
adjacent supplementary angles adjacent supplementary angles

50 °

130 °

U X

MLV W

K N

68 °

0

112 °

27

O

RQ P

63

O

T R

S

45

45

45

45

501 Geometry Questions