Answer:
h = 20 cm
Explanation:
The area of a trapezoid is given by
A = 1/2 (b1+b2) *h
where b1 and b2 are the two bases
We are given a =400 and b1 =27 and b2 =13
400 = 1/2 (27+13) *h
400 = 1/2 (40) *h
400 = 20h
Divide each side by 20
400/20 = 20h/20
20 =h