document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1095380>Question 1095380</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is an application problem using polynomial equations/functions:  \"An open box with a rectangular base is to be made from a rectangular piece of cardboard by cutting out a square of x inches from each corner and turning up the sides.  The dimensions of the cardboard are 25 inches by 20 inches.  Write a function in one variable for the volume of the box.\"\r<BR>\n" );
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document.write( "I assume the dimensions given are for the cardboard prior to the squares being cut from each corner, so this is what I came up with:\r<BR>\n" );
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document.write( "V = lwh<BR>\n" );
document.write( "l = 25 - 2x<BR>\n" );
document.write( "w = 20-2x<BR>\n" );
document.write( "h = x<BR>\n" );
document.write( "so:<BR>\n" );
document.write( "f(x) = (25-2x)(20-2x)x<BR>\n" );
document.write( "f(x) = 4x^3 - 90x^2+500x\r<BR>\n" );
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document.write( "But I'm pretty sure this is incorrect.  I'm stumped.  Can you show me where I've gone wrong?\r<BR>\n" );
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document.write( "Thank you for any help you can give me. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #709893 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=709893\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br>You are \"pretty sure\" your work is incorrect...<br><BR>\n" );
document.write( "I am POSITIVE that you are mistaken there.<br><BR>\n" );
document.write( "Your work is exactly what it should be.<BR>\n" );
document.write( "Note that there is no need to expand the formula into a polynomial form; the factored form is sufficient, and for many applications would even be more meaningful and therefore better. </SPAN>\n" );
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