If A, B, and C are collinear, then point B is between A and C if and only if AB+BC=AC

D is in the interior of angle ABC if and only if m

If M is the midpoint of segment AB, then AM and MB are congruent.

If two angles form a linear pair, then they are supplementary angles.

Angles complementary to the same angle or to congruent angles are congruent.

If the noncommon sides of two adjacent angles form a right angle, then the angles are complementary.

Angles complementary to the same angle or to congruent angles are congruent.

If two angles are vertical angles, then they are congruent.

If two parallel lines are cut by a transversal, then each pair of corresponding angles is congruent.

If two parallel lines are cut by a transversal, then each pair of alternate interior angles is congruent.

If two parallel lines are cut by a transversal, then each pair of consecutive interior angles is supplementary

If two parallel lines are cut by a transversal, then each pair of alternate exterior angles is congruent.

In a plane, if a line is perpendicular to one of two parallel lines, then it is perpendicular to the other.

If two lines are cut by a transversal so that corresponding angles are congruent, then the lines are parallel.

If given a line and a point not on the line, then there exists exactly one line through the point that is parallel to the given line.

If two lines in a plane are cut by a transversal so that a pair of alternate exterior angles is congruent, then the two lines are parallel.

If two lines in a plane are cut by a transversal so that a pair of consecutive interior angles is supplementary, then the lines are parallel

If two lines in a plane are cut by a transversal so that a pair of alternate interior angles is congruent, then the lines are parallel

In a plane, if two lines are perpendicular to the same line, then they are parallel.

If given a line and a point not on the line, then there exists exactly one line through the point that is perpendicular to the given line.

The sum of the measures of the angles of a triangle is 180.

The measure of an exterior angle of a triangle is equal to the sum of the measures of the remote interior angles.

If two angles of one triangle are congruent to two angles of a second triangle, then the third angles of the triangles are congruent.

If three sides of one triangle are congruent to three sides of a second triangle, then the triangles are congruent.

If two sides and the included angle of one triangle are congruent to two sides and the included angle of a second triangle, then the triangles are congruent.

If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent.

If two angles and the nonincluded side of one triangle are congruent to the corresponding two angles and side of a second triangle, then the two triangles are congruent.

If the legs of one right triangle are congruent to the corresponding legs of another right triangle, then the triangles are congruent.

If the hypotenuse and acute angle of one right triangle are congruent to the hypotenuse and corresponding acute angle of another right triangle, then the triangles are congruent.

If one leg and an acute angle of one right triangle are congruent to the corresponding leg and acute angle of another right triangle, then the triangles are congruent.

If the hypotenuse and a leg of one right triangle are congruent to the hypotenuse and corresponding leg of another right triangle, then the triangles are congruent.

If two sides of a triangle are congruent, then the angles opposite those sides are congruent.

If two angles of a triangle are congruent, then the sides opposite those angles are congruent.

If a point is on the perpendicular bisector of a segment, then it is equidistant from the endpoints of the segment.

If a point is equidistant from the endpoints of a segment, then it is on the perpendicular bisector of the segment.

The circumcenter of a triangle is equidistant from the vertices of that triangle.

If a point is on the bisector of an angle, then it is equidistant from the sides of the angle.

If a point in the interior of an angle is equidistant from the sides of the angle, then is is on the angle bisector.

The incenter of a triangle is equidistant from the sides of the triangle.

The centroid of a triangle is two thirds of the distance from each vertex to the midpoint of the opposite side.

The measure of an exterior angle of a triangle is greater than the measure of either of its corresponding remote interior angles.

The sum of the lengths of any two sides of a triangle is greater than the length of the third side.

If two triangles have two pairs of congruent sides, and the included angle of the first is larger than the included angle of the second, then the third side of the first is larger

## Show Comments