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2 cubes have all sides and bases painted.
One cube's side length is 4 cm longer than the other cube's side length. If the larger cube needed 56 square cm more paint than the smaller cube, what is the side length of the smaller cube?

 if the side length  of the smaller cube is x, 
   then the side length of the bigger cube is x+4

   surface area of the smaller cube is 6x^2 square cm, 
   surface area of the larger cube is  6(x+4)^2 = 6x^2 + 48x + 96 square cm

  the equation is 
   6x^2 + 48x + 96 = 6x^2 + 56
   48x +96 = 56
   48x = -40
    x = -5/6

I am confused, how can a side length be negative?

Math
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math123
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    I read the problem to have each cube have $5$ faces painted-the base and the four sides but not the top. This does not solve the problem. It changes $x$ to $-\frac 35$ but it is still negative. The math part of your solution is correct, our disagreement is reading the English. I would ask for an explanation from the problem setter. +1 for showing your work and identifying the issue. – Ross Millikan Dec 21 '19 at 03:25
  • Did the source of the problem have a proposed solution? Maybe one could reverse engineer that to see what solver did... as you note something is off. – coffeemath Dec 21 '19 at 03:56
  • This is what they call "the problem has no solution". – Conifold Dec 21 '19 at 04:49

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