Angles Review

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

Give an example of a pair of complementary angles.

Back

81° and 9° are complementary angles because 81° + 9° = 90°.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are always equal.

Front

If m∠1 = 30°, what is m∠3 if they are vertical angles?

Back

m∠3 = 30° because vertical angles are equal.

Front

What is the sum of the interior angles of a triangle?

Back

The sum of the interior angles of a triangle is always 180°.

Front

What is the sum of the interior angles of a quadrilateral?

Back

The sum of the interior angles of a quadrilateral is always 360°.

Front

How do you calculate the sum of the interior angles of a polygon?

Back

The sum of the interior angles of a polygon with n sides is given by the formula: (n - 2) × 180°.

Front

What is the sum of the interior angles of a nonagon?

Back

The sum of the interior angles of a nonagon (9 sides) is 1260°.

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.