Question 1209840
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x = length
k = width
k = height


volume of rectangular block = length*width*height
V = x*k*k
V = x*k^2


If length + width = 2 meters, then,
x+k = 2
k = 2-x


So,
V = x*k^2
V = x*(2-x)^2
V = x*(2-x)(2-x)
V = x*(4-4x+x^2)
V = x^3-4x^2+4x


I don't know where your textbook got the x/16 from.
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