document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=298834>Question 298834</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In the problem 3x+4y=6 5x+2y=-4  how do you know that you need to multiply by -2?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #214926 by </B><A HREF=/tutors/aboutme.mpl?userid=TX911><B>TX911(36)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TX911><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=TX911><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=214926\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Because when using the addition method:\r<BR>\n" );
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document.write( "3x+4y=6<BR>\n" );
document.write( "5x+2y=-4\r<BR>\n" );
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document.write( "we need to solve for y first because if we solve for x first we're going to be dealing with fractions which we want to avoid in the interest of simplicity. So what do we need to multiply the second equation by in order to set the y's to where they cancel each other? That's right, -2 because 2*-2 =-4. Now when we add the top equations 4y to the bottom equations -4y we get zero which now let's us solve for y.  Don't forget to multiply the other numbers in the second equation by -2 as well. It should look like -2(5x+2y=-4) and our result would be -10x-4y=-8.\r<BR>\n" );
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