Math Theorems/Postulates

Right Angles Congruency Theorem

Any two right angles are congruent.

Supplement Postulate

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

Third Angle Theorem

If two angles of one triangle are congruent to two angles of another, then the third angles is congruent.

PSSIAS Theorem

If two parallel lines are cut by a transversal, then Same-Side Interior Angles are Supplementary.

PAEC Theorem

If two parallel lines are cut by a transversal, then alternate exterior angles are congruent

PAIC Theorem

If two parallel lines are cut by a transversal, then alternate interior angles are congruent

PCAC Postulate

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

Supplement Theorem

Supplement of congruent angles are congruent

Angles Sum of a point Postulate

The Sum of a measure of the angle at a point is 360

Exterior Angle Theorem

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

Regular Polygon Interior Angle Theorem

The measure of each angle of a regular n-gon is (n - 2) 180 / N

Vertical Angles Theorem

The measure of the vertical angles are equal or the vertical angles are congruent

The Triangle Interior Angle Theorem

The sum of the degree measures of the angle of a triangle is 180.

Quadrilateral Interior Angle Theorem

The sum of the measure of the angles of a convex quadrilateral is 360.

Polygon Interior Angle Theorem

The sum of the measures of the angle of a convex polygon with n sides is (n - 2) 180.

Polygon Exterior Angle Theorem

The sum of the measures of the exterior angles, one at each vertex, of any convex polygon is 360.

Complement Theorem

Complements of congruent angles are congruent