Respuesta :

9514 1404 393

Answer:

  A.  18

Step-by-step explanation:

The area of a trapezoid is given by the formula ...

  A = 1/2(b1 +b2)h

Here, the parallel bases have lengths 3 and 9. The height is 3, so the area is ...

  A = 1/2(3 +9)(3) = 18

The area of the trapezoid is 18 square units.