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33 terms

Geometry Unit 3 Vocab

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Parallel Lines
Coplanar, equidistant, non-intersecting lines
Parallel Planes
Equidistant, non-intersecting planes
Skew Lines
Non-coplanar, non-intersecting lines
Transversal
Line that intersects two or more lines in a plane at different points
Interior Angles
Inside angles of two lines intersected by a transversal
Exterior Angles
Outside angles of two lines intersected by a transversal
Alternate Interior Angles
Inside angles of two lines intersected by a transversal and on opposite sides of the transversal (angles 3,6 and 4,5)
Alternate Exterior Angles
Outside angles of two lines intersected by a transversal and on opposite sides of the transversal (angles 2,7 and 1,8)
Consecutive Interior Angles
Inside angles of two lines intersected by a transversal and on the same side of the transversal (angles 4,6 and 3,5)
Corresponding Angles
Pair of angles formed by two lines and a transversal consisting of an interior angle and an exterior angle that have different vertices and that lie on the same side of the transversal (angles 2,6 and 1,5 and 4,8 and 3,7)
Corresponding Angles Postulate
Two parallel lines cut by a transversal create corresponding angles that are congruent.
Alternate Interior Angles Theorem
Two parallel linescut by a transversal create pairs of alternate interior angles that are congruent.
Consecutive Interior Angles Theorem
Two parallel lines cut by a transversal create pairs of consecutive interior angles that are supplementary.
Alternate Exterior Angles Theorem
Two parallel lines cut by a transversal create pairs alternate exterior angles that are congruent.
Perpendicular Transversal Theorem
If a transversal is perpendicular to one of the two parallel lines, then it is perpendicular to the other
Corresponding Angles Converse Postulate
Equal, two lines are cut by a transversal so that corresponding angles are congruent then the lines are parallel
Alternate Interior Angles Converse
Negative Reciprocals, 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 so that consecutive interior angles are supplementary, then the lines are parallel
Alternate Exterior Angles Converse
if two lines are cut by a transversal so that the alternate exterior angles are congruent, then the lines are parallel
Flow Proof
like a two column proof but the statements are connected by arrows to show how each statement comes from the ones before it
Vertical angles
if two angles sides form two pairs of opposite rays
Linear pair
two adjacent angles whoes noncommon sides are opposite
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.
Congruent angles
Angles that have the same measure
perpendicular lines
two lines that intersect to form a right angle
oblique lines
when two lines intersect and are not perpendicular
coincident lines
when the graphs of two lines are the same or coincidentally on top of one another
linear pair postulate
If two angles form a linear pair, then they are supplementary (sum to 180)
vertical angles theorem
vertical angles are congruent
slope
= (y₂-y₁) / (x₂-x₁) [rise over run]
slope of parallel lines
the slopes of Parallel lines are the same
m = m
slope of perpendicular lines
negative reciprocals (flip and change signs)
m --> -1/m