document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=815725>Question 815725</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Solving Problems with Quadratic Equations<BR>\n" );
document.write( "21. An open-topped box is to be made from a rectangular piece of tin measuring 50 cm by 40 cm by cutting squares of equal size from each corner. The base area is to be 875 cm^2.<BR>\n" );
document.write( "a) Draw a diagram representing the information.<BR>\n" );
document.write( "b) What is the side length of the squares being removed?<BR>\n" );
document.write( "c) What is the volume of the box?<BR>\n" );
document.write( "Thanks1!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #491182 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=491182\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the base dimensions are 50 by 40\r<BR>\n" );
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document.write( "squares of side x are cut at the corners\r<BR>\n" );
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document.write( "the length will be (50-2x)<BR>\n" );
document.write( "width will be (40-2x)\r<BR>\n" );
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document.write( "The area = 875 cm^2\r<BR>\n" );
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document.write( "(50-2x)((40-2x)=875\r<BR>\n" );
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document.write( "2000-180x+4x^2=875\r<BR>\n" );
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document.write( "4x^2-180x+1125=0\r<BR>\n" );
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document.write( "Find the roots of the equation by quadratic formula							<BR>\n" );
document.write( "							<BR>\n" );
document.write( "a=	4	,	b=	-180	,	c=	1125<BR>\n" );
document.write( "							<BR>\n" );
document.write( "b^2-4ac=	32400	+	-18000				<BR>\n" );
document.write( "b^2-4ac=	14400						<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%09sqrt%28%0914400%09%29=%09120%09 ALIGN=MIDDLE  ALT=\"%09sqrt%28%0914400%09%29=%09120%09\"   DISABLED_style= \"max-width:90%; height:auto;\" >		<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "x1=(	180	+	120	)/	8		<BR>\n" );
document.write( "x1=	37.50						<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >							<BR>\n" );
document.write( "x2=(	180	-120	) /	8			<BR>\n" );
document.write( "x2=	7.50						\r<BR>\n" );
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document.write( "the side of square cut = 7.50 cm\r<BR>\n" );
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document.write( "Volume of box =50*40*7.50\r<BR>\n" );
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document.write( "=1500 cm^2 </SPAN>\n" );
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