A lot is in the shape of a trapezoid. The sum of the bases is 180 feet. If the area of the lot is 8,100 square feet, what is the distance across the lot, i.e. the altitude of the figure?
Well let me solve it like this: As we know  the area is h(a+b)/2, So what we do is: h (180/2) = 8100 90h = 8100 h = 90 I hope this is easy to understand
