document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=140236>Question 140236</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0130519685/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\">  A oicture frame measures 12cm by 20cm. 84cm(squared) of picture shows inside the frame. Find the width of frame </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102212 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=102212\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A picture frame measures 12 cm by 20 cm. 84 cm(squared) of picture shows inside the frame. Find the width of frame<BR>\n" );
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document.write( "Let x = width of the frame<BR>\n" );
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document.write( "then the dimension of the picture would be: (20-2x) by (12-2x)<BR>\n" );
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document.write( "The area of the picture:<BR>\n" );
document.write( "(20-2x)*(12-2x) = 84<BR>\n" );
document.write( "FOIL<BR>\n" );
document.write( "240 - 40x - 24x + 4x^2 = 84<BR>\n" );
document.write( "Arrange as a quadratic equation:<BR>\n" );
document.write( "4x^2 - 64x + 240 - 84 = 0<BR>\n" );
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document.write( "4x^2 - 64x + 156 = 0<BR>\n" );
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document.write( "Simplify, divide by 4:<BR>\n" );
document.write( "x^2 - 16x + 39 = 0<BR>\n" );
document.write( "Factor<BR>\n" );
document.write( "(x-13)(x-3) = 0<BR>\n" );
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document.write( "Two solutions, however,<BR>\n" );
document.write( "x = +3 cm; is the only one that makes sense.<BR>\n" );
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document.write( "Width of the frame: 12 - 2(3) = 6 cm<BR>\n" );
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document.write( "Check solution by finding the area using the picture dimensions: L = 20-2(3) = 14<BR>\n" );
document.write( "14 * 6 = 84 sq/cm as given<BR>\n" );
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document.write( "did I make sense to you here? Let me know, please. </SPAN>\n" );
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