I don't know the area of a parallelogram off the top of my head but you can use the area of the rectangle and the area of the triangle and add those. The area of the triangle is 1/2*base*height and use the pythagorean theorem to find the base. 3² + b² = 5²; 9 + b² = 25; b² = 16; b = 4. The area of the triangle is 1/2*4*3 or 6 in. Since there are two of them, the total area of the triangles are 12 in. The area of the rectangle is length*width or (12 - 4) * 3 which is 8 * 3 or 24in. Add these areas together to get 36in total
