Trapezoid ABCD has a height of 40ft and an area of 3140 square feet. Base 1 is 14 feet less than twice base 2. How long is base 1?
base2 --- x
base1 ---- 2x-14
area of trap = (1/2)(sum of parallel sides)(height)
3140 = (1/2)(x + 2x-14)(40)
157 = 3x - 14
3x = 171
x = 57
so base2 is 57, and base1 = 2(57)-14 = 100
check:
area = (1/2)(57 + 100)(40) = 3140