Corresponding Angles Postulate
If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent
Alternate Interior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent.
Alternate Exterior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent
Consecutive Interior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary.
converse
EX: If it is cloudy outside, then it is raining.
swaps the if-then parts of the statement
EX: If it is raining, then it is cloudy outside
Corresponding Angles Converse
if corresponding angles are congruent, then the lines are parallel
alternate interior angles converse
If alternate interior angles are congruent, then the lines are parallel
Alternate Exterior Angles Converse Theorem
If two lines are cut by a transversal so the alternate exterior angles are congruent, then the lines are parallel.
Consecutive Interior Angles Converse
If two lines are cut by a transversal so the consecutive interior angles are supplementary, then the lines are parallel.
theorem
A mathematical statement which we can prove to be true
postulate
a statement that is accepted as true without proof
defintion of congruence
If 2 figures are congruent, then they are equal in measure
**allows you to change equal signs to congruence signs and vice versa