document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=285611>Question 285611</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If the sides of a square are lenghtened by 8 cm, the area<BR>\n" );
document.write( "becomes 144cm^2, find the length of a side of the original square,\r<BR>\n" );
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document.write( "The length of a side of the original square is ------- cm. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #207018 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=207018\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> formula for area of a square is:\r<BR>\n" );
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document.write( "a = x^2\r<BR>\n" );
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document.write( "Increase the side by 8 cm and the formula becomes:\r<BR>\n" );
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document.write( "144 = (x+8)^2\r<BR>\n" );
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document.write( "You want to find the length of the side of the original square, which is x.\r<BR>\n" );
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document.write( "(x+8)^2 = x^2 + 16x + 64\r<BR>\n" );
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document.write( "Equation becomes:\r<BR>\n" );
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document.write( "144 = x^2 + 16x + 64\r<BR>\n" );
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document.write( "Subtract 144 from both sides of this equation to get\r<BR>\n" );
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document.write( "0 = x^2 + 16x - 80\r<BR>\n" );
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document.write( "This factors out to be:\r<BR>\n" );
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document.write( "0 = (x+20) * (x-4)\r<BR>\n" );
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document.write( "You get x = -20 or x = 4\r<BR>\n" );
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document.write( "x can't be negative so x has to be 4.\r<BR>\n" );
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document.write( "When x = 4, the area is 4^2 = 16<BR>\n" );
document.write( "When x = 4 + 8 = 12, the area is 12^2 = 144\r<BR>\n" );
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document.write( "Numbers check out so answer is that the side of the original square is 4 cm.\r<BR>\n" );
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