document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=256779>Question 256779</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If x + y = 5 and x^2 + 3xy + 2y^2 = 40, find the value of (2x + 4y). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188825 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=188825\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you have 2 equations.\r<BR>\n" );
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document.write( "they are\r<BR>\n" );
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document.write( "x + y = 5<BR>\n" );
document.write( "x^2 + 3xy + 2y^2 = 40\r<BR>\n" );
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document.write( "solve for y in the first equation to get y = 5-x\r<BR>\n" );
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document.write( "substitute for y in the second equation to get:\r<BR>\n" );
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document.write( "x^2 + 3x(5-x) + 2(5-x)^2 = 40\r<BR>\n" );
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document.write( "simplify to get:\r<BR>\n" );
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document.write( "x^2 + 15x - 3x^2 + 2 * (25 - 10x + x^2) = 40\r<BR>\n" );
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document.write( "simplify further to get:\r<BR>\n" );
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document.write( "x^2 + 15x - 3x^2 + 50 - 20x + 2x^2 = 40\r<BR>\n" );
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document.write( "combine like terms to get:\r<BR>\n" );
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document.write( "-5x + 50 = 40 \r<BR>\n" );
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document.write( "subtract 50 from both sides of eqution to get:\r<BR>\n" );
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document.write( "-5x = 40 - 50 = -10\r<BR>\n" );
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document.write( "multiply both sides by -1 to get:\r<BR>\n" );
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document.write( "5x = 10\r<BR>\n" );
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document.write( "divide both sides by 5 to get:\r<BR>\n" );
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document.write( "x = 2\r<BR>\n" );
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document.write( "substitute in first equation to get:\r<BR>\n" );
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document.write( "x + y = 5 becomes 2 + y = 5 becomes y = 3\r<BR>\n" );
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document.write( "you have x = 2 and y = 3\r<BR>\n" );
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document.write( "2x + 4y = 2*2 + 4*3 = 4 + 12 = 16\r<BR>\n" );
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document.write( "your answer is (2x + 4y) = 16.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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