If the measure of the angles is the same the angles are congruent.
Angle Addition Postulate
Substitution Property
Replace a known variable for it's value in an expression or equation.
What do you know about the measure of VERTICAL ANGLES?
The measures are equal. They are the same.
Definition of Angle Bisector
A line the divides an angle into TWO EQUAL angles.
Definition of Right Angle
If the measure of an angle is 90 degrees then it is a right angle.
Transitive Property
If <A = <B, and <B = <C, then <A = <C.
What do you know about the measure of CONGRUENT ANGLES?
They are the same. They are equal.
Definition of Perpendicular
Lines that intersect to form 90 degree angles.
Definition of Complementary Angles
Two angles whose sum is 90 degrees.
Definition of a Midpoint
A point that splits a line into TWO EQUAL parts.
What do you know about the measure of angles formed by an ANGLE BISECTOR?
The are equal. Half of the whole angle.
Definition of Supplementary Angles
If two angles have a sum of 180 degrees, then they are supplementary.
Vertical Angles
A pair of angles that are on opposite sides of the vertex.
Angles are equal in measure.
Congruent Supplements Theorem
If two angles are supplementary to the same angle then they are equal.
What do you know about the measure of angles that are SUPPLEMENTARY?
They add together to equal 180 degrees.
Linear Pair Theorem
If two or more angles form a straight line then they are a linear pair and equal to 180 degrees.
Complement Theorem
Angles that form a right angle together.
Congruent Complements Theorem
If two angles are complementary to the same angle then they are equal.
What do you know about the measure of angles formed by PERPENDICULAR LINES?
The angles are 90 degrees.