Theorem:
Vertical angles are congruent.
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Postulates

DescriptionExample
1. Ruler Postulate:
The points on a line can be matched one to one with the real numbers. The real numbers that correspond to a point is the coordinate of the point. The distance between points A and B, written as AB, is the absolute value of the difference between the coordinates A and B.
2.Segment Addition Postulate:
If B is between A and C, then AB+BC=AC, then B is between the coordinates of A and C.
3.Angle Addition Postulate:
If P is in the interior of RST, then mRSP+mPST=mRST.
4.Through any two points there exists exactly one line.
5.A line contains at least two points.
6.If two lines intersect, then their intersection is exactly one point.
7.Through any three noncollinear points there exists exactly one plane.
8.A plane contains at least three noncollinear points.
9.If two points lie in a plane, then the line containing them lies in the plane.
10.If two planes intersect, then their intersection is a line.

Theorems

1.Right Angle Congruence Theorem:
All right angles are congruent.
2.Congruent Supplements Theorem:
If two angles are supplementary to the same angle (or to congruent angles) then the two angles are congruent.
3.Congruent Complements Theorem:
If two angles are complementary to the same angle (or to congruent angles) then the two angles are congruent.
5.Alternate Interior Angles:
If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent.
6.Consecutive Interior Angles:
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary.
7.Alternate Exterior Angles:
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent.
8.Perpendicular Transversal:
If a transversal is perpendicular to one of two perpendicular lines, then it is perpendicular to the other.
9.Alternate Interior Angles Converse:
If two lines are cut by a transversal so that alternate interior angles are congruent, then the lines are parallel.
10.Consecutive Interior Angles Converse:
If two lines are cut by a transversal so that consecutive interior angles are supplementary, then the lines are parallel.

Copyright to Gaile Anne Patan�e