Answer: 8 cm
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Work Shown:
Let's solve for h in the formula below
A = 0.5*h*(b1+b2)
240 = 0.5*h*(24+36)
240 = 0.5*60*h
240 = 30h
30h = 240
h = 240/30
h = 8
The height of the trapezium is 8 cm. This is the distance between the two parallel sides.