Geometry Chapter 2

Description
Long version
Short version
Definition of right angle
If an angle’s measure is 90, then it is a right angle.
Right angles measure 90.
Definition of straight angle
If an angle’s measure is 180, then it is a straight angle.
Straight angles measure 180.
Definition of congruent angles
If two angles have the same measure, then they are congruent.
Congruent angles have the same measure.
Definition of congruent segments
If two segments have the same length, then they are congruent.
Congruent segments have the same length.
Definition of angle bisector
If a ray divides an angle into two congruent angles, then it is an angle bisector.
A bisector divides an angle into congruent angles.
Definition of segment bisector
If a point/ray/segment/line divides a segment into two congruent segments, then it is a segment bisector.
A bisector divides a segment into congruent segments.
Definition of angle trisector
If two rays divide an angle into three congruent angles, then the rays are angle trisectors.
Trisectors divide an angle into congruent angles.
Definition of segment trisector
If two point/rays/segments/lines divide a segment into three congruent segments, then they are segment trisectors.
Trisectors divide a segment into congruent segments.
Definition of complementary angles
If two angles sum to a right angle, then they are complementary.
Complementary angles sum to a right angle.
Definition of supplementary angles
If two angles form a linear pair, then they are supplementary.
Supplementary angles form a linear pair.
Definition of perpendicular ()
If two lines/rays/segments intersect at right angles, then they are perpendicular.
Perpendicular lines/rays/segments form a right angle.
Theorem 1
If two angles are right angles, then they are congruent.
Right angles are congruent.
Theorem 2
If two angles are straight angles, then they are congruent.
Straight angles are congruent.
Theorem 4/Theorem 6
If two angles are supplementary/complementary to the same angle, then they are congruent.
Angles supplementary/complementary to the same angle are congruent.
Theorem 5/Theorem 7
If two angles are supplementary/complementary to congruent angles, then they are congruent.
Angles supplementary/complementary to congruent angles are congruent.
Theorem 8/Theorem 9 – Addition Property
If a segment/an angle is added to two congruent segments/angles, then the sums are congruent
Sums of congruent segments/angles and a segment/an angle are congruent.
Theorem 10/Theorem 11 –
Addition Property
If two congruent segments/angles are added to two