160 likes | 447 Views
Ch 8.4. Properties of Rhombuses, Rectangles, and Squares. A rhombus is a parallelogram that has four congruent sides. That means that the opposite sides must also be parallel. The diagonals of a rhombus form perpendicular lines. What is a rhombus?. The diagonals bisect the interior angles.
E N D
Ch 8.4 Properties of Rhombuses, Rectangles, and Squares
A rhombus is a parallelogram that has four congruent sides. That means that the opposite sides must also be parallel. The diagonals of a rhombus form perpendicular lines. What is a rhombus?
The diagonals bisect the interior angles. Rhombus cont…
A rectangle is a parallelogram with 4 right angles. Therefore, opposite sides must also be parallel. The diagonals of a rectangle are congruent. Rectangles
A square is a parallelogram with 4 right angles AND 4 congruent sides. Because a parallelogram has parallel opposite sides, a square has parallel opposite sides. Squares
A trapezoid is a quadrilateral with 1 pair of parallel sides. Trapezoids
Can any square be a rectangle? • Yes! • Can any rectangle be a square? • No! • Can any square be a rhombus? • Yes! • Can any rectangle be a rhombus? • No! Can it be…?
Suppose you have a rhombus ABCD… When are the following true? Sometimes, never, or always B m<A = m<C ALWAYS m<B = m<C Sometimes A C m<B = m<D ALWAYS AB = BC ALWAYS D AB = DC ALWAYS
Suppose you have a rectangle ABCD… when are the following true? Always? Never? Sometimes? B A M<A = m<C ALWAYS m<B = m<C ALWAYS D C m<B = m<D ALWAYS Sometimes AB = BC AB = DC ALWAYS
First classify the quadrilateral then find x and y Rhombus 5x + 6 = 8x 6 = 3x 2 = x < Q and < P should be supplementary! 12y – 1 + 97 = 180 12y + 96 = 180 12y = 84 y = 7
First classify the quadrilateral then find x and y Square 2x + 1 = 4x - 7 2x + 8 = 4x 8 = 2x 4 = x < KLN and < NLM should be complementary! 7y + 3 + 45 = 90 7y + 48 = 90 7y = 42 y = 6
Given that WXYZ is a rhombus…what do we know about the figure? The diagonals bisect the interior angles. A rhombus is a parallelogram that has four congruent sides. That means that the opposite sides must also be parallel. The diagonals of a rhombus form perpendicular lines. 12.5 34º 56º 56º 34º 12.5 12.5 10.4 34º 56º 56º Z Y 12.5 Cos(56) = 7/x 7/Cos(56) = x 12.5 = x SOH CAH TOA!
The figure below is a rectangleFind the missing angles and sides m<TPQ m<PST m<PTQ PS PR HINT: PTQ is what kind of triangle?
www.classzone.com Practice, Practice, Practice Chapter 8-4 Laptops