document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=668278>Question 668278</A>: <I><SPAN STYLE=\"word-break: break-all;\"> x+3y=18<BR>\n" );
document.write( "3x-4y=2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415431 by </B><A HREF=/tutors/aboutme.mpl?userid=gwendolyn><B>gwendolyn(128)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=gwendolyn><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=gwendolyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415431\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+3y=18<BR>\n" );
document.write( "3x-4y=2<BR>\n" );
document.write( "First, let's isolate x in the first equation by subtracting 3y from both sides:<BR>\n" );
document.write( "x+3y=18<BR>\n" );
document.write( "x=18-3y<BR>\n" );
document.write( "Then, we can plug in this value of x into the second equation:<BR>\n" );
document.write( "3x-4y=2<BR>\n" );
document.write( "3(18-3y)-4y=2<BR>\n" );
document.write( "Now we can distribute the 3 to the value in parentheses:<BR>\n" );
document.write( "54-9y-4y=2<BR>\n" );
document.write( "Next, we combine like terms (the constants and the y values):<BR>\n" );
document.write( "54-13y=2<BR>\n" );
document.write( "52-13y=0<BR>\n" );
document.write( "52=13y<BR>\n" );
document.write( "To get the value of y, all we have to do is divide by 13:<BR>\n" );
document.write( "4=y<BR>\n" );
document.write( "And then we can plug this value into the first equation to find x:<BR>\n" );
document.write( "x+3y=18<BR>\n" );
document.write( "x+3*4=18<BR>\n" );
document.write( "x+12=18<BR>\n" );
document.write( "x=6\r<BR>\n" );
document.write( "\n" );
document.write( "Finally, let's check these values by plugging them into the second equation:<BR>\n" );
document.write( "3x-4y=2<BR>\n" );
document.write( "3*6-4*4=2<BR>\n" );
document.write( "18-16=2<BR>\n" );
document.write( "2=2\r<BR>\n" );
document.write( "\n" );
document.write( "This equation checks, so we know that y=4 and x=6. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );