Respuesta :

Answer:

42 ft²

Step-by-step explanation:

Area of trapezoid = ½(a + b)h

a = 9 ft

b = 3 + 9 = 12 ft

h = √(5² - 3²) = 4 ft (pythagorean theorem)

Plug in the values

Area = ½(9 + 12)*4

Area = ½(21)*4 = 42 ft²