1) this is total area of two triangle
area of a triangle=1/2*b*h
A=1/2*9*4
A=18 inches^2
multiply by 2 because there are two triangle with same measure
2A=2*18=36 inches^2
3) this is a area of rectangle and a triangle and then subtract
A2=9.3x7.8= 72.54
area of triangle A1=1/2*7.8 *3.3=12.87
A2-A1=59.69 mm^2
5) now u ca do it
