Question

What is the area of the following trapezoid in square feet?

A-B:
135 ft2
165 ft2
82.5 ft2
64.9 ft2

Answer 1

135 ft^2 (first answer choice)

Explanation:

Convert the length of the 7 yd base to feet: 21 ft.

Then the average length of the trapezoid is (15 ft + 21 ft)/2 = 36/2 ft = 18 ft.

The area of the trapezoid is then (average length)(height), or

A = (18 ft)(7.5 ft) = 135 ft^2 (first answer choice)

Answer 2

82.5 ft²

Explanation:

The area (A) of a trapezoid is calculated as

A =
`(1)/(2)` h (b₁ + b₂)

where h is the perpendicular height and b₁, b₂ the parallel bases

Here h = 7.5, b₁ = 7 and b₂ = 15 , then

A =
`(1)/(2)` × 7.5 × (7 + 15) = 0.5 × 7.5 × 22 = 82.5 ft²