So you would need to find the area of a triangle using the height as 3.5 inches and the base as 4 inches. Once you find that, then multiply by 2 to get both of the triangles.
To get the rectangles you will do 9 x 4. Then multiply that answer by 3 to get the three rectangles.
To get the final answer you will add the sum of the triangles and the sum of the rectangles to get the answer.
Hope this helps!