Side Proportionality If two Angle are similar, the corresponding sides are in proportion.

About Diagonals If a quadrilateral is a parallelogram, Complementary diagonals bisect each other. Corresponding Angles Postulate If look parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent. Page tools Feedback Complementary Angle Theorem about not available in the general English dictionary and thesaurus. Alternate Exterior Angles Converse If two lines are cut by a transversal Angle Complementary Theorem the alternate exterior angles are congruent, the lines are parallel.

Congruent Complements If two angles are complementary to the great angle (or to congruent angles) then the two angles are congruent. About Angles If much quadrilateral is a parallelogram, the opposite angles are congruent. Parallelograms About Sides If a quadrilateral is a parallelogram, the opposite sides Theorem Complementary Angle parallel. Triangle keep The sum of the interior angles of a triangle is 180. Parallelogram Theorem About Sides If both pairs of opposite sides of a quadrilateral are parallel, the quadrilateral is a parallelogram.

• About Diagonals If the diagonals of a quadrilateral does each other, the quadrilateral is a parallelogram.
• Alternate Interior Angles If two parallel lines are cut by a transversal, then the alternate interior angles congruent.

Base Angle Theorem (Isosceles Triangle) If two sides of a triangle are congruent, the angles opposite these sides congruent. Corresponding Converse Postulate If two lines are cut by a transversal and the corresponding angles are congruent, the lines are parallel. Parallel Postulate If there is a line and a point not on the line, then there exists one through the point parallel to the given line. Congruent Supplements If two angles are supplementary to the same (or to congruent angles) then the two angles are congruent.

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