Angle and Line Postulates and Properties

Front

What are complementary angles?

Back

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

Front

What is the Segment Addition Postulate?

Back

The Segment Addition Postulate states that if point B is between points A and C, then AB + BC = AC.

Front

What is the Angle Addition Postulate?

Back

The Angle Addition Postulate states that if point B is in the interior of angle AOC, then m∠AOB + m∠BOC = m∠AOC.

Front

What is the Definition of Congruent segments?

Back

Two segments are congruent if they have the same length.

Front

What is the Definition of Midpoint?

Back

A midpoint of a segment is the point that divides the segment into two equal parts.

Front

What is the Substitution Property of Equality?

Back

The Substitution Property of Equality states that if two values are equal, one can be substituted for the other in any expression.

Front

What are vertical angles?

Back

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

Front

What is the Definition of Angle Bisector?

Back

An angle bisector is a ray that divides an angle into two equal parts.

Front

What is the Definition of Complementary Angles?

Back

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

Front

If m∠A + m∠B = 70° and m∠B = 40°, what is m∠A?

Back

m∠A = 70° - 40° = 30°.