Vector and range values

Large stockpile of 10cmx10cm sheets. What is the largest volume you can create by cutting out x centimeters by x centimeters from each corner of the sheet and then folding up the sides. Create a plot of volume versus x max~=75

What I have so far

for a=[0:0.5:10]
    volume=a*(10-2*a)^2
end

[Rik]

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