document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=75916>Question 75916</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0130501417/algebrahomeworkh>Prentice Hall Algebra </A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> How do you solve <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=3x+%2B+1 ALIGN=MIDDLE  ALT=\"y=3x+%2B+1\"   DISABLED_style= \"max-width:90%; height:auto;\" > <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x=3y+%2B+1 ALIGN=MIDDLE  ALT=\"+x=3y+%2B+1\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Using substitution. Our teacher has given us this practice with no review from her.  I don't know where to start using substitution.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #54511 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=54511\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> substitution means taking a quantity from one equation and substituting its equivalent into another equation\r<BR>\n" );
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document.write( "In your case, taking the y from the first equation and substituting into the second equation gives x=3(3x+1)+1...every \"y\" in the second equation is replaced by its equivalent from the first equation \"3x+1\"... so x=9x+3+1...or x=-1/2\r<BR>\n" );
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document.write( "noting the symmetry of the two equations (they are identical, with the variables switched) means that y will also be -1/2.  You could confirm this by practicing a substitution from the second equation to the first </SPAN>\n" );
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