A cube has a surface area of 54 cm2. The volume of the cube, in cm3, is
Pick one
Solution
Substituting x=4 into 3x+2y we get, 3(4)+2y=12+2y.
Since this expression 12+2y is equal to 30, then 2y must equal 30−12 or 18. If 2y=18, then y is 18÷2 or 9.
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