Question

Please help me out with this

Answer 1

81.75 ft²

Explanation:

The area (A) of a trapezoid is calculated using the formula

A =
`(1)/(2)` h (a + b)

where a, b are the parallel bases and h is the perpendicular height

Calculate h using the right triangle and the sine ratio

sin30° =
`(opposite )/(hypotenuse)` =
`(h)/(10)`

Multiply both sides by 10

10 × sin30° = h, thus

h = 5

a = 12 and b = 8.7 + 12 = 20.7, hence

A =
`(1)/(2)` × 5 × (12 + 20.7)

= 0.5 × 5 ×32.7

= 81.75 ft²