Let’s assume that a and b are two parallel sides of a trapezoid. This means that a = 8 cm, b = 10 cm, and h = 9 cm.By using the centroid of a trapezoid formula, we will get:X = {b + 2a / 3 (a + b)} x hX = {10 + 2 (8) / 3 (8 + 10)} x 9X = {26 / 54} x 9X = 13 / 3X = 4.33