1. The Area of a Trapezoid Lesson 11.3 b2b2 b1b1 h

2. Theorem 102: The area of a trapezoid equals one-half the product of the height and the sum of the bases. A trap = h(b 1 + b 2 ) Where b 1 is the length of one base, b 2 is the length of the other base, and h is the height.

3. Prove that the area of a trapezoid is ½ h(b1 + b2) by the following method: Group A  Draw a diagonal and use the two triangles formed. Group B  Draw altitudes and use the rectangle and triangles formed.

4. Median of a Trapezoid The line segment joining the midpoints of the non-parallel sides of a trapezoid is called the median of the trapezoid. CL Z U X E Y

5. Theorem 103: The measure of the median of a trapezoid equals the average of the measures of the bases. M = (b 1 + b 2 ) Where b 1 is the length of one base and b 2 is the length of the other base.

6. Theorem 104: The area of a trapezoid is the product of the median and the height. A trap = Mh Where M is the length of the median and h is the height.

7. Find the area. 6in. 7in. 60˚ > > 1.Find h. 2.h = 3 √ 3 3.Find x. 4.3 5.Find b 1. 6.3 + 3 + 7 = 13 h x A = ½ h(b 1 + b 2 ) A = ½ (3 √ 3)(13 + 7) A =30 √ 3 in 2

8. Find the median & area of the trapezoid. M 6 12 14 Median = ½(b 1 + b 2 ) M = ½(14 + 6) M = 10 A = Mh A = 10(12) A = 120