You can put this solution on YOUR website! If you know the height and area of a trapezoid can you find the lengths of its bases?
AREA OF A TRAPEZOID=(1/2)(HT)(SUM OF PARALLEL SIDES)...SUPPOSE
AREA=40,HT=8...THEN
40=(1/2)*8*(SUM OF PARALLEL SIDES)
SUM OF PARALLEL SIDES=2*40/8=10..
SO WE CAN KNOW THE SUM OF THE 2 PARALLL SIDES ,BUT NOT SIZE OF EACH SIDE.THEY COULD BE 1&9..OR..2&8...OR....5&5...ETC...