document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=282267>Question 282267</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help solving a linear system problem using linear comblinations.  The problem is 7x-4y=-3 and 2x+5y=-7.  I got (1,1), but when I use them they don't work right.  First I multiplied 5(7x-4y)=5(-3), 35y-20y=-15, 43y=43, y-1.<BR>\n" );
document.write( "The next part I multiplied 2(2x+5y)=2(-7), 14x-8y=-6, -14x-35y=49, 43y=43, y=1.<BR>\n" );
document.write( "I'm not sure where I need to go with all of this.  Please help me. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #204965 by </B><A HREF=/tutors/aboutme.mpl?userid=nyc_function><B>nyc_function(2741)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nyc_function><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=nyc_function><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=204965\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 7x-4y=-3...Equation A<BR>\n" );
document.write( "2x+5y=-7...Equation B\r<BR>\n" );
document.write( "\n" );
document.write( "7x - 4y = -3\r<BR>\n" );
document.write( "\n" );
document.write( "-4y = -7x - 3\r<BR>\n" );
document.write( "\n" );
document.write( "y = (7/4)x + 3/4\r<BR>\n" );
document.write( "\n" );
document.write( "Plug this into Equation B to find x.\r<BR>\n" );
document.write( "\n" );
document.write( "2x + 5((7/4)x + 3/4) = -7\r<BR>\n" );
document.write( "\n" );
document.write( "2x + (35/4)x + 15/4 = -7\r<BR>\n" );
document.write( "\n" );
document.write( "2x(4) + 4[(35/4)x + 15/4] = -7(4)\r<BR>\n" );
document.write( "\n" );
document.write( "8x + 35x + 3 = -28\r<BR>\n" );
document.write( "\n" );
document.write( "43x = -28 - 3\r<BR>\n" );
document.write( "\n" );
document.write( "43x = -31\r<BR>\n" );
document.write( "\n" );
document.write( "x = -31/43\r<BR>\n" );
document.write( "\n" );
document.write( "==================================\r<BR>\n" );
document.write( "\n" );
document.write( "Now, plug this value for x into either equations above to find y.\r<BR>\n" );
document.write( "\n" );
document.write( "I will use Equation A but you can also use B.\r<BR>\n" );
document.write( "\n" );
document.write( "7(-31/43) - 4y = -3\r<BR>\n" );
document.write( "\n" );
document.write( "-217/43 - 4y = -3\r<BR>\n" );
document.write( "\n" );
document.write( "-4y = -3 + 217/43\r<BR>\n" );
document.write( "\n" );
document.write( "y = (-3 + 217/43)/-4\r<BR>\n" );
document.write( "\n" );
document.write( "y = -22/43\r<BR>\n" );
document.write( "\n" );
document.write( "SOLUTION POINT: (-31/43, -22/43)....This is the answer.\r<BR>\n" );
document.write( "\n" );
document.write( "The point (1,1) is not the answer. \r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );