Answer: 168 square feet
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Step-by-step explanation:
The front triangular face is a triangle with base 8 and height 6. Its area is
A = 0.5*base*height
A = 0.5*8*6
A = 24 square feet
The back triangular face is also 24 square feet since these are the base faces of the prism. The base faces are always congruent. It might help to imagine this figure is turned on its side.
The slanted lateral face is a rectangle of length 10 ft and width 5 ft, so its area is L*W = 10*5 = 50 square feet
The rectangular face on the left is 6 ft by 5 ft giving an area of 6*5 = 30 square feet.
Lastly, the bottom rectangular face is 8 ft by 5 ft giving an area 8*5 = 40 square feet
Overall, the total surface area is: 24+24+50+30+40 = 168 square feet
We just add up all the individual areas of each face to get the total surface area.