Volume of Prism: Length & Width (y^3-y, y-1)

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To determine the length and width of a swimming pool with a volume of y^3-y and height of y-1, the volume formula V=lbh is applied. By substituting the known values, the equation simplifies to y(y+1)=lw after factoring. The possible dimensions for the pool are either y units long and (y+1) units wide or (y+1) units long and y units wide. Without further information, the specific assignment of length and width cannot be determined. The discussion clarifies that y can be any real value greater than 1, not limited to whole integers.
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if a swimming pool has a volume of y^3-y and a height of y-1 then what is the length and width?
 
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The volume of a prism is

V=lbh

And so in your case, V=y^3-y and h=y-1 so plug these in, can you then figure out what l and b must be? Hint: Factorize.
 
I have it set up as:
y(y-1)(y+1)=lw(y-1) which I then divide by (y-1) to get
y(y+1)=lw and then I am stuck
 
Markg1997 said:
I have it set up as:
y(y-1)(y+1)=lw(y-1) which I then divide by (y-1) to get
y(y+1)=lw and then I am stuck

Yer pool is either y units long and (y+1) units wide or (y+1) units long and y units wide. Without additional information, you can't tell which dimension is which.
 
That's assuming that all measurements are whole integers which was not given.
 
HallsofIvy said:
That's assuming that all measurements are whole integers which was not given.
This doesn't assume whole integers at all. y could be any real value greater than 1.
 
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