1. Area of a Trapezoid

2. Find the area of each figure. 1. 2. Find each missing measure. 3. Area = 100 in 2 4. Area = 25.2 cm 2 x 10.5 h 2.3 ft 2 10

3.  Quadrilateral: 4 sides  Trapezoid: Quadrilateral with only one pair of parallel sides.

4. b1b1 b2b2 h is height b 1 is base #1 b 2 is base #2

5.  http://www.youtube.com/watch?v=9jxMI4O4jb0&NR=1 http://www.youtube.com/watch?v=9jxMI4O4jb0&NR=1  http://www.mathplayground.com/howto_area_trapezoid.html http://www.mathplayground.com/howto_area_trapezoid.html  http://www.youtube.com/watch?v=-_HxRZ4keTU&feature=related http://www.youtube.com/watch?v=-_HxRZ4keTU&feature=related  http://www.mathopenref.com/trapezoidarea.html http://www.mathopenref.com/trapezoidarea.html  http://www.youtube.com/watch?v=2PhMRRBVvEg&NR=1 http://www.youtube.com/watch?v=2PhMRRBVvEg&NR=1  nerdy  http://www.youtube.com/watch?v=W2Ghl33EdOs&NR=1 http://www.youtube.com/watch?v=W2Ghl33EdOs&NR=1

6. Find the area of the trapezoid.  Write the trapezoid area formula.  Substitute all known values.  Add numbers in parentheses.  Multiply.  The area of the trapezoid is 28 ft 2.

7. Find the height of the trapezoid. The trapezoid’s area is 17.5 cm 2.  Write the trapezoid area formula.  Substitute all known values.  Add numbers in parentheses.  Multiply on the right side.  Divide by 7  The height of the trapezoid is 2.5 cm.

8. 1. Find the area of the trapezoid. 2. The area of the trapezoid is 82 square inches. Find the height. 9 m 6.2 m 5 m 17 in 24 in h

9.  How can the area of a trapezoid be explained or broken down using other geometric shapes and area formulas?  Explain how the “average” is used in the formula for area of a trapezoid.

10. Target: Understand and use the trapezoid area formula

12. Nakisha painted a large trapezoid-shaped mural. The area of the mural is 88 square feet. The longer base is 20 feet. The height is 6.4 feet. Find the length of the missing base.  Draw the figure.  Write the formula.  Substitute given information.

13. Nakisha painted a large trapezoid-shaped mural. The area of the mural is 88 square feet. The longer base is 20 feet. The height is 6.4 feet. Find the length of the missing base.  Multiply and 6.4.  Distribute 3.2.  Subtract 64 from each side.  Divide by 3.2  The length of the missing base is 7.5 feet.