by Oshi

(Dubai)

First, let us state the formula for calculating the area of a trapezoid:

Where

Substitute the values we have into the formula:

91 = (AB + CD)/2 X 8

Knowing that CD is longer than AB by 8cm, we could include that information in the equation like this:

91 = (AB + (AB + 8))/2 X 8

Let's solve the equation!

91 = (2AB + 8)/2 X 8

91 = (AB + 4) X 8

91 = 8AB + 32

91 - 32 = 8AB

79 = 8AB

AB = 79/8

AB =

CD = AB + 8

CD =