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A square base box has a volume of 200 cm^3, find the dimensions if the height is 3 cm more than the length
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According to the condition, for the squared base side x, we have this cubic equation
x^2*(x+3) = 200 cubic units (the volume).
One solution is easy to guess: x = 5.
Now, since the left side of the equation is monotonically increasing function, this solution x = 5 is UNIQUE:
there are no other solutions.
ANSWER. The dimensions are 5 cm for the square base and 8 cm for the height.
Solved.