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Bell Work. Find the area of each figure. 13 in. 11 in. 10 in. 18 m. 32 m. A= bh A= (18)( 32 ) A= 288 m². A = bh A = (10)(13) A = 130 in². Area of Trapezoids. Area of a Trapezoid.
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Bell Work Find the area of each figure. 13 in 11 in 10 in 18 m 32 m A= bh A= (18)(32) A= 288 m² A = bh A = (10)(13) A = 130 in²
Area of a Trapezoid Given the formula for the area of a parallelogram we are going to use that information to discover the formula for the area of a trapezoid. Watch carefully not to miss it!
h (b1 + b2) Area of a Trapezoid Copy the trapezoid, flip it over, and put it next to the original. It makes a parallelogram. We are going to use the area of a parallelogramto find the area of a trapezoid. Notice that the trapezoid is half the area of the parallelogram. It takes two trapezoids to make one parallelogram.
h (b1 + b2) Area of a Trapezoid Notice that the trapezoid is half the area of the parallelogram. How do we find half the area? Hint: Think of area of a triangle. Trapezoid Parallelogram A = (b1 + b2) • h
Area of a Trapezoid Area of Trapezoid 2 in 4 in A = (b1 + b2) •h 4 in 3 in 6 in A = (2 + 6) •3 Perimeter of Trapezoid A = (8) •3 P= 4 + 4 + 2 + 6 A = 4 •3 P= 16 in A = 12 in²
Area of a Trapezoid Area of Trapezoid 3 m 5 m A = (b1 + b2) •h 4 m 8 m A = (3 + 8) •4 A = (11) •4 A = 22 m² A = (44)
You Try! Find the area and perimeter 12 in 5 in 4 in 6 in 7 in 4in 4in 7 in 5 in A = 24 in² A = 59.5 in² P= 25 in P= 22 in