Answer: ac+bc=49.5cm^2
Explanation:
Question: If the area of the trapezoid is 99 cm^2 , what is the value of the missing measure ?
Area of trapezoid = area of parallelogram + area of triangle = upper base × height + (lower base - upper base) × height ÷ 2 = (upper base + lower base) × height ÷ 2 （Área del trapezoide = área del paralelogramo + área del triángulo = base superior × altura + (base inferior - base superior) × altura ÷ 2 = (base superior + base inferior) × altura ÷ 2）
(a+b)*c/2=99cm^2
ac+bc=99/2
ac+bc=49.5cm^2