(B) first calculate the are of the whole rectangle
Then calculate the area of the two triangles . On top right the height will be 5 ft and the base will be 4 ft
And on the bottom left the height will be 4ft and the base will be 10ft
After calculating the area of two triangles and one rectangle
You need to subtract the are of triangles from the area of the rectangle
And what ever comes will be your answer .
I hope you understood the procedure .
Thanks
