Answer:
89m
Step-by-step explanation:
First, find the area of the rectangle (ignoring the missing triangle inside). The area of the rectangle is its base times its height, which is 8*13=104.
Next, find the area of the triangle. The area of the triangle is its base times height, divided by two.
The width of one side of the rectangle is 13, and the width of the side of the rectangle is 8 (4 + 4). Therefore, subtract 8 from 13 and the missing section in the side of the rectangle is 5. 5 is equal to the base of the triangle.
The height of the triangle is given, which is 6. As stated before, the area of a triangle is its base times height divided by two, which is 5*6/2 in this case. The area of the triangle is equal to 15.
Now, subtract the area of the triangle from the area of the rectangle. 104-15=89.