document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=313834>Question 313834</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve the systems of equations by the substitution method:<BR>\n" );
document.write( "5x-4y+=30-5x<BR>\n" );
document.write( "3x+6=x+5y+15\r<BR>\n" );
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document.write( "I added 5x to both sides to get all variables on one side and got \r<BR>\n" );
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document.write( "10x-4y=30 now I not sure where to go from here to solve for y....Please help!\r<BR>\n" );
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document.write( "lilchikcadee@msn.com\r<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 #224399 by </B><A HREF=/tutors/aboutme.mpl?userid=unlockmath><B>unlockmath(1688)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=unlockmath><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=unlockmath><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=224399\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hello,<BR>\n" );
document.write( "Let's set up both equations <BR>\n" );
document.write( "5x-4y+=30-5x<BR>\n" );
document.write( "3x+6=x+5y+15 <BR>\n" );
document.write( "like this:<BR>\n" );
document.write( "10x-4y=30<BR>\n" );
document.write( "-3x-5y=9<BR>\n" );
document.write( "Since substitution is required let's set the first equation like this:<BR>\n" );
document.write( "x=2/5(y)+3<BR>\n" );
document.write( "Now substitute this into the second equation to get:<BR>\n" );
document.write( "-3(2/5y+3)-5y=9 Rewritten as:<BR>\n" );
document.write( "-6/5(y)-9-5y=9 Add 9 and combine like terms to get:<BR>\n" );
document.write( "-19/5 y=18 Multiply both sides by -5/19 to get:<BR>\n" );
document.write( "y=-90/31<BR>\n" );
document.write( "Plug this into the first to get:<BR>\n" );
document.write( "10x-4(-90/31)=30 This works out to:<BR>\n" );
document.write( "x=57/31<BR>\n" );
document.write( "You can now plug these answers into both and it works out. <BR>\n" );
document.write( "Make sense?<BR>\n" );
document.write( "RJ<BR>\n" );
document.write( "www.math-unlock.com<BR>\n" );
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