1. Lesson 11-2 Day 2 Area of Trapezoids and Rhombi

2. Area of Trapezoids & Rhombi Trapezoid Area A = ½* h* (b 1 + b 2 ) h is height (altitude) b 1 and b 2 are bases (JK & LM) (bases are parallel sides) Rhombus Area A = ½ * d 1 * d 2 d 1 and d 2 are diagonals A B C D h b1b1 b2b2 JK LM N d1d1 d2d2

3. Example 1 h 20 12 JK L M N 60° 14 Find the area of trapezoid JKLM

4. Example 2-4b Trapezoid DEFG has an area of 120 square feet. Find the height of DEFG. Example 2

5. Example 3 A B C D 5 Find the area of rhombus ABCD 5 4 3 Is there another way to find the area of a rhombus?

6. Example 2-4a Rhombus RSTU has an area of 64 square inches. Find US if RT = 8 inches. Example 4

7. Example 2-4c b.Trapezoid QRST has an area of 210 square yards. Find the height of QRST. a. Rhombus ABCD has an area of 81 square centimeters. Find BD if AC = 6 centimeters. Example 5

8. Example 2-5b INTERIOR DESIGN This window hanging is composed of 12 congruent trapezoidal shapes. The total area of the design is 216 square inches. Each trapezoid has bases of 4 and 8 inches. Find the height of each trapezoid. Example 6

9. Example 7 Find the area of the trapezoid given the following coordinates (-1,8), (5,8), (3,4), and (1,4). Find the area of the trapezoid given the following coordinates (-1,8), (5,8), (3,4), and (1,4).

10. Example 8 Find the area of the rhombus with the following coordinates (-4,3), (-2,4), (0,3) and (-2,2) Find the area of the rhombus with the following coordinates (-4,3), (-2,4), (0,3) and (-2,2)

11. Summary & Homework Summary: Summary: The formula for the area of a triangle can be used to find the areas of many different figures The formula for the area of a triangle can be used to find the areas of many different figures Congruent figures have equal areas Congruent figures have equal areas Homework: Homework: pg 605 (10, 11, 15-18, 30-33) pg 605 (10, 11, 15-18, 30-33)