Geometry Proofs

Addition Property

If a = b, then a + c = b + c

Subtraction Property

If a = b, then a - c = b - c

Multiplication Property

If a = b, then ac = bc

Division Property

If a = b, then a/c = b/c

Reflexive Property

For any real #, a = a

Symmetric Property

If a = b, then b = a

Transitive Property

If a = b and b = c, then a = c

Substitution Property

If a = b, then b can be substituted in for a

Parallel Lines

 lines that will never intersect since they have congruent slopes

Perpendicular Lines

lines that intersect to create 90 degree angles

Point of Concurrency

the point of intersection for more than 2 lines

Transversal

a line that intersects two lines at two different points

Vertical Angles

two angles that share a vertex but do not share any sides