Answer: 216 square inches of wrapping paper
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Work Shown:
x = side length of cube = 6 inches
SA = surface area of cube
SA = 6x^2
SA = 6*6^2
SA = 6*36
SA = 216 square inches
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side note: if you have a rectangular box that isn't a cube (ie the length, width, and/or height aren't all the same), then you would use this formula to get the surface area
SA = 2*(L*W+L*H+W*H)
where L,W,H are the length, width and height respectively.