Parallelogram & Kite & Triangle Midsegment Properties

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Parallelogram & Kite & Triangle Midsegment Properties http://www.mathsisfun.com/definitions/parallelogram.html Parallelogram Diagonals Theorem A diagonal of a parallelogram separates it into two congruent triangles. Parallelogram Definition: A Parallelogram is a flat shape with opposite sides parallel and equal in length. D C A B Given: ABCD is a parallelogram Prove: ABC CDA STATEMENTS REASONS Parallelogram Opposite Angles Corollary The opposite angles of a parallelogram are congruent. (Lesson 5.5) Parallelogram Consecutive Angles Corollary The consecutive angles of a parallelogram are supplementary. (Lesson 5.5) Parallelogram Opposite Sides Corollary The opposite sides of a parallelogram are congruent. B D, A C (Lesson 5.5) mB mC 180 Parallelogram Diagonals Corollary The diagonals of a parallelogram bisect each other. mA mD 180 (Lesson 5.5) AE CE, BE DE http://www.mathsisfun.com/definitions/kite.html Kite Definition - A quadrilateral (4-sided flat shape with straight sides) with two distinct pairs of congruent adjacent sides. Kite Angles Theorem The nonvertex angles of a kite are congruent. Kite Diagonals Corollary The diagonals of a kite are perpendicular. Kite Diagonal Bisector Corollary The diagonal connecting the vertex angles of a kite is the perpendicular bisector of the other diagonal. Kite Angle Bisector Corollary The vertex nonvertex angles of a kite are bisected by a diagonal. angles http://www.mathopenref.com/trianglemidsegment.html Midsegment of a Triangle Definition A line segment joining the midpoints of two sides of a triangle. A triangle has 3 possible midsegments. Three Midsegments Theorem A midsegment of a triangle is parallel to the third side and half the length of the third side. Three Midsegments Corollary: The three midsegments of a triangle divide it into four congruent triangles. k STATEMENTS REASONS .

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Build a Tetrahedral Kite
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