Answer: 6 square units
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Work Shown:
x = side length = 1 unit
SA = surface area of cube
SA = 6x^2
SA = 6*1^2
SA = 6*1
SA = 6
The surface area of the cube is 6 square units.
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Side note:
In general, each face is x*x = x^2 units in area, and there are 6 of those faces. This is why the general surface area is 6x^2. In this case, each face is 1 square unit, so all 6 faces lead to a total of 6 square units.