1. © 2010 Pearson Prentice Hall. All rights reserved Parallelograms, Trapezoids, and Rhombuses § 7.3

2. Tobey & Slater, Basic College Mathematics, 6e2 Quadrilaterals A quadrilateral is a four-sided figure. Parallelogram Rhombus Both pairs of opposite sides are parallel. All four sides have the same length.

3. Tobey & Slater, Basic College Mathematics, 6e3 Quadrilaterals Rectangle Parallelogram Rhombus Square Quadrilateral

4. Tobey & Slater, Basic College Mathematics, 6e4 Perimeter of a Parallelogram The perimeter (P) of a parallelogram is the distance around the parallelogram. This is also true for a rhombus. Example: Find the perimeter of the parallelogram. P = 2l + 2w = 2(11) + 2(7) = 22 + 14 = 36 meters 11 m 7 m

5. Tobey & Slater, Basic College Mathematics, 6e5 Area of a Parallelogram The area (A) of a parallelogram is found by multiplying the base times the height. Any side of the parallelogram can be considered the base (b). The height (h) is the shortest distance between the base and the side opposite the base. height base height base

6. Tobey & Slater, Basic College Mathematics, 6e6 Area of a Parallelogram Example: Find the area of the following parallelogram. A = bh = (11)(7.5) = 82.5 m 2 11 m 7.5 m

7. Tobey & Slater, Basic College Mathematics, 6e7 Area of a Rhombus Example: Find the area of the following rhombus. A = bh = (9)(6.3) = 56.7 ft 2 9 ft 6.3 ft

8. Tobey & Slater, Basic College Mathematics, 6e8 Trapezoids A trapezoid is a four-sided figure with two parallel sides (bases). base

9. Tobey & Slater, Basic College Mathematics, 6e9 Perimeter of a Trapezoid The perimeter (P) of a trapezoid is the distance around the trapezoid. Example: Find the perimeter of the trapezoid. P = 7 + 6.5 + 10 + 7.2 = 30.7 inches 10 in 7 in 6.5 in7.2 in

10. Tobey & Slater, Basic College Mathematics, 6e10 Area of a Trapezoid A height (h) of a trapezoid is the distance between the two parallel sides. The area of a trapezoid is one-half the height times the sum of the bases. base = B base = b height = h

11. Tobey & Slater, Basic College Mathematics, 6e11 Area of a Trapezoid Example: Find the area of the trapezoid. 8 mm 5.5 mm 6 mm