Which statement describes complementary angles?

Which statement describes complementary angles?

• A. Two angles whose sum is 180 degrees.
• B. Two angles that add up to 90 degrees.
• C. Two angles that share a vertex and a side.
• D. Two angles that are vertically opposite.

Answer: (B)

Complementary angles are two angles whose measures add up to 90 degrees. When you put them together, they form a right angle. For example, a 30-degree angle and a 60-degree angle are complementary because 30 + 60 = 90. This is why the statement describing complementary angles is the correct one. To connect this to other ideas: angles that sum to 180 degrees are called supplementary. Angles that share a vertex and a side are adjacent, but sharing a side doesn’t by itself define the sum. Vertically opposite angles are the angles opposite each other when two lines cross and they are equal to each other, not defined by a 90-degree sum.

Complementary angles are two angles whose measures add up to 90 degrees. When you put them together, they form a right angle. For example, a 30-degree angle and a 60-degree angle are complementary because 30 + 60 = 90. This is why the statement describing complementary angles is the correct one.

To connect this to other ideas: angles that sum to 180 degrees are called supplementary. Angles that share a vertex and a side are adjacent, but sharing a side doesn’t by itself define the sum. Vertically opposite angles are the angles opposite each other when two lines cross and they are equal to each other, not defined by a 90-degree sum.