Answer:
577.50
Step-by-step explanation:
You need to add all the areas of the separate pieces together, so the triangles are:
Triangle: 7 (12) (1/2), but you have 2 of them so don't divide by 2, just 7(12) so that part is 84
Top flap is 15(7) = 105
Middle is 15(12) = 180
Bottom is 15(13.89) = 208.35
Add them all together 84+105+180+208.35 = 577.50
