Area of a trapezoid is found according to the following formula: A = (a + b) * h / 2. You can notice that for a trapezoid with a = b (and hence c = d = h), the formula gets simplified to A = a * h, which is exactly the formula for the area of a rectangle.

Area of a trapezoid is found according to the following formula: A = (a + b) * h / 2. You can notice that for a trapezoid with a = b (and hence c = d = h), the formula gets simplified to A = a * h, which is exactly the formula for the area of a rectangle.