SOLUTION: The surface area of a cube is 864 cm². What is the length of one of its edges?

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Question 1161647: The surface area of a cube is 864 cm². What is the length of one of its edges?
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
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Surface area of the cube = 864cm%5E2
6a%5E2+=+864cm%5E2
a%5E2=+864cm%5E2%2F6
a%5E2+=+144cm%5E2
a+=+sqrt%28144cm%5E2%29
a+=+12cm

Answer by ikleyn(52903) About Me  (Show Source):
You can put this solution on YOUR website!
.

Hint N 1.  A cub has 6 congruent faces. They are squares.

           So, find the area of one (of each) square face, first.



Hint N 2.  The area of a square is the square of its side.

           Knowing the area of the face square, find its side.

When you complete, report your progress and your answer.