Answer: 920
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Step-by-step explanation:
The front face is a triangle with area of base*height/2 = 15*8/2 = 60 square feet.
The back face is identical to the front face, so we have another 60 square feet.
The left rectangular wall is 20 ft by 8 ft tall. Its area is 20*8 = 160 ft^2
The right slanted rectangular face is 20 ft by 17 ft. Its area is 20*17 = 340 ft^2
Lastly, the bottom rectangle floor is 15 ft by 20 ft to give an area of 15*20 = 300 ft^2
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To summarize so far
- Front face = 60 ft^2
- Back face = 60 ft^2
- Left face = 160 ft^2
- Right slanted face = 340 ft^2
- Bottom floor = 300 ft^2
Add up those areas to get the overall surface area.
60+60+160+340+300 = 920