document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=397096>Question 397096</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do u work this problem out? Its system of equations <BR>\n" );
document.write( "3x+4y=12<BR>\n" );
document.write( "Y=-2x+10<BR>\n" );
document.write( "  <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 #281535 by </B><A HREF=/tutors/aboutme.mpl?userid=Sarpi><B>Sarpi(32)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Sarpi><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=Sarpi><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=281535\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">                       Solution<BR>\n" );
document.write( "This is a kind of two simultaneous equation.<BR>\n" );
document.write( "Step 1: <BR>\n" );
document.write( "Arrange the equation as follows;<BR>\n" );
document.write( "3x+4y = 12 -------------- eqn 1<BR>\n" );
document.write( "    y = 10-2x ----------- eqn 2<BR>\n" );
document.write( "(I just interchanged the position of eqn 2 but it is the same as y = -2x+10)\r<BR>\n" );
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document.write( "Step 2:<BR>\n" );
document.write( "By the substitution method, you make one of the variable x or y the subject in one of the eqn.<BR>\n" );
document.write( "Luckily, we have y has the subject in eqn 2.<BR>\n" );
document.write( "            ie y = 10 - 2x ---------- eqn 3.<BR>\n" );
document.write( "Step 3:<BR>\n" );
document.write( "You substitute or put the eqn 3 into eqn 1. Note you cannot put eqn 3 into its derived eqn (ie eqn 2).<BR>\n" );
document.write( " => where y should be replaced by 10-2x in eqn 1<BR>\n" );
document.write( " ie  in eqn 1; <BR>\n" );
document.write( "          3x+4y = 12<BR>\n" );
document.write( "    3x+4(10-2x) = 12    \"10-2x is put in bracket because it is multiplying by 4\"<BR>\n" );
document.write( "   3x+40-8x     = 12     \"multiplication; 4*10 =40 and 4*-2x=-8x\"<BR>\n" );
document.write( "          3x-8x = 12- 40       \"grouping of liked variables(numbers with x on     one side\"                    <BR>\n" );
document.write( "            -5x = -28               <BR>\n" );
document.write( "            x   = -28/-5     \"we obtain this by dividing both side by -5\"<BR>\n" );
document.write( "            <BR>\n" );
document.write( "             x  = 28/5 or 5.6<BR>\n" );
document.write( "Step 4:<BR>\n" );
document.write( "Now that we have found x, we move on to find y using one of the eqns(1 or 2). Thus it is easy to use eqn 2 or 3 in order to find y.<BR>\n" );
document.write( "              => y = 10-2x<BR>\n" );
document.write( "                 y = 10-2(5.6)<BR>\n" );
document.write( "                 y = 10-11.2<BR>\n" );
document.write( "                 <BR>\n" );
document.write( "                 y = -1.2<BR>\n" );
document.write( "Hence the solution to the problem is x=5.6 and y=-1.2<BR>\n" );
document.write( "By checking;<BR>\n" );
document.write( "3x+4y=12<BR>\n" );
document.write( "3(5.6)+4(-1.2) will exactly give you 12.\r<BR>\n" );
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document.write( "And I hope you will easily understand my steps. Cheers!<BR>\n" );
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