Chapter 3 Flashcards
Intersecting lines
Coplanar and have exactly one point in common
Oblique
Intersecting lines that do not meet at a right angle
Skew lines
Two Lines are skew if they do not lie in the same plane
Transitivity of parallel lines
If two lines are parallel to the same line, then they are parallel to each other
Property of perpendicular lines
If two coplanar lines are perpendicular to the same line, then they are parallel to each other
Two distinct lines intersect…
Then their intersection is exactly 1 point
Parallel postulate
If there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line
Perpendicular postulate
If there is a line and a point not on the line, then there is exactly one line through the point perpendicular to the given line
If two lines are perpendicular…
Then they intersect to form four right angles
All right angles are…
Congruent
If two lines intersect to form a pair of adjacent congruent angles…
Then the lines are perpendicular
Transversal
A line that intersects two or more coplanar lines at different points.
Corresponding angles
Two angles are corresponding if they occupy corresponding positions
Alternate interior angles
Two angles are alternate interior angles if they lie between L and M on opposite sides of t.
Alternate exterior angles
Two angles are alternate exterior angles, if they lie outside of L and M on opposite sides of t
Consecutive interior angles
Two angles are consecutive interior angles if they live between L and M on the same side of t
Corresponding angles postulate
If two parallel lines are cut by a transversal, then the pairs of corresponding ankles are congruent
Alternate interior angles thm
If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent
Consecutive interior angle thm
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary
Alternate exterior angles thm
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent.
Parallel lines
Coplanar lines that do not intersect
Perpendicular transversal theorem
If a transversal is perpendicular to one of two parallel lives is perpendicular to the second
Responding angles converse postulate
If two lines are cut by transversal a soda corresponding angles are congruent, then the lines are parallel
Alternate interior angles converse
If two lines are cut by a transversal so that alternate interior angles are congruent, then the lines are parallel
Consecutive interior angles converse
If two lines are cut by a transversal it so that consecutive interior angles are supplementary then the lines are parallel
Alternate exterior angles converse
If two lines are cut by a transversal’s sold out alternate exterior angles are congruent, then the lines are parallel
