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Find the measures of each exterior angle and interior angle for each regular polygon:. 1. decagon. Warm Up. Section 8.4a Properties of Rhombuses, Rectangle, and Squares. Parallelogram. Rectangle. Rhombus. Both pairs of opposite sides are parallel. Square. Quadrilateral.
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Find the measures of each exterior angle and interior angle for each regular polygon: 1. decagon Warm Up
Section 8.4a Properties of Rhombuses, Rectangle, and Squares
Parallelogram Rectangle Rhombus Both pairs of opposite sides are parallel. Square Quadrilateral A quadrilateral is a four-sided figure.
Rhombus • Four congruent sides • Diagonals bisect a pair of opposite angles • Diagonals are perpendicular
Rectangle • Four right angles B A • Diagonals are congruent D C Square • Four right angles and four congruent sides (it’s a rhombus and a rectangle)
It’s Parallelogram v.s Rhombus
Parallelogram Rhombus • Opposite sides are parallel • Four congruent sides • Opposite sides are congruent • Diagonals are perpendicular • Opposite angles are congruent • Diagonals bisect a pair of opposite angles • Diagonals bisect each other • Consecutive angles are supplementary
Theorem 8.12: A parallelogram is a rhombus if and only if eachdiagonal bisects a pair of opposite angles. A B D C Theorem 8.11: A parallelogram is a rhombus if and only if its diagonals are perpendicular.
It’s Parallelogram v.s Rectangle
Parallelogram Rectangle A B • Opposite sides are parallel • Four right angles • Opposite sides are congruent D C • Diagonals are congruent • Opposite angles are congruent • Diagonals bisect each other • Consecutive angles are supplementary
Theorem 8.13: A parallelogram is a rectangle if and only if eachdiagonal are congruent. A B D C
Quadrilateral Parallelogram Rhombus Rectangle Square
Examples For any rhombus QRST, decide whether the statement is always or sometimes true. Draw a sketch and explain your reasoning. Q R • Q S • Q R T S
For any rectangle ABCD, decide whether the statement is always or sometimes true. Draw a sketch and explain your reasoning. A B • AB CD • AB BC D C
Quadrilateral Name each quadrilateral – PARALLELOGRAM, RECTANGLE, RHOMBUS, and SQUARE – for which the statement is true. Parallelogram 1. Its equiangular and equilateral 2. Opposite sides are congruent 3. The diagonals bisect opposite angles Rhombus Rectangle 4. Four right angles 5. All consecutive angles are supplementary Square
Quadrilateral Parallelogram Rhombus Rectangle Square