Proving Perpendicular/parallel. Chapter 3 Flashcards
If two parallel lines are cut by a transversal, which angles are congruent?
Corresponding, alternate exterior and interior, and consecutive interior angles
Alternate interior angels 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 angels are congruent
Consecutive interior angles theorem
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary
Corresponding angles converse
If two lines are cut by a transversal so the corresponding angles are congruent, then the lines are parallel
Alternate interior and exterior converse
If two lines are cut by a transversal so the alternate exterior and interior angels 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
Perpendicular postulate
- If two lines intersect to form a linear pair of congruent angles, then the lines are perpendicular.
- If two lines are perpendicular, then they intersect to form 4 right angles
- If two sides of adjacent acute angles are perpendicular, then the angles are complementary
- If a transversal is perpendicular to one of two parallel lines, then it is perpendicular to the other
- If two lines are perpendicular to the same line then they are parallel