document.write( "Question 498879: A box is to be removing four identical squares (with side length X) from each corner of a retangular piece of card then folding up the resulting flaps. If the piece of card is 40cm by 30cm write down a fundtion for the volume of the resulting box in terms of X. What sort of funtion is it ( quadratic, Rational, cubic or...). What is the domain of this funtion?\r
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Algebra.Com's Answer #337243 by Earlsdon(6294) $\"\"$ $\"About$

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After removing the corner squares of side x, the remainder of the sides of the original rectangular cardboard will measure (40-2x) and (30-2x) and the height of the finished box will be x.
\n" ); document.write( "The volume of this box can be expressed as:
\n" ); document.write( " $\"V+=+%2840-2x%29%2830-2x%29x\"$ If you multiply these factors, you'll get:
\n" ); document.write( " $\"V+=+4x%5E3-140x%5E2%2B1200x\"$
\n" ); document.write( "Clearly, this is a \"cubic\" function.
\n" ); document.write( "From a practical standpoint, x cannot equal or exceed half the length of the smaller side of the original rectangle, otherwise, you could not make a box.
\n" ); document.write( "So x can take on values: $\"0%3Cx%3C15\"$ \n" ); document.write( "

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