You could draw out a word diagram
Well if you take the room being 20 x 24. Thats 480 feet. But you want how large in 1/2 inch. 1/2 inch is 1/24 of a foot. So if we take 480 feet being 1 and times it by 24. (480 x 24) You get 11,520 half inches. Brainliest would be much appreciated if you feel its deserved.
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