Answer:
6 sqft × $21.5 = $129
Explanation:
Area of a trapezoid is just average the top and bottom 2 + 6 = 8÷2 = 4 the times this by the height. So toss out those 2.5 sides (the not-parallel sides) we don't need them; we don't care about them. Use the straight up and down height measurement.
4 × 1.5
= 6 ft^2
Then times by 21.50 to find the cost. 6×21.5=129