Transitive Property of Equality

if a = b and b = c, then a = c

Symmetric Property of Equality

if a = b, then b = a

Reflective Property of Equality

a = a

Distributive Property

a(b + c) = ab + ac

Segment Addition Postulate

If B is inside L AXC, then mL AXB + mL BXC = mL AXC

Angle Addition Postulate

If point B is on the line segment AC, then AB + BC = AC

Linear Pair Theorem

Angles that add up to 180 degrees

Vertical Angles Theorem

If two angles are vertical, then they are congruent

Acute Angles

an angle that measures less than 90 degrees

Right Angles

an angle that is equal to 90 degrees

Obtuse Angle

an angle that measures between 90 degrees and 180 degrees

Straight Angle

an angle that measures 180 degrees

Supplementary Angles

If two angles form a straight line, they add up to 180

Complementary Angles

Angles that add up to 90 degrees

Congruent Angles

Two angles that are equal in measure

Adjacent Angles

Two angles that share a side

Bisector

A ray or line segment that cuts shape, line, or angle with 2 equal parts

Midpoint

The middle point of a line segment, which divides the segment into two equal parts