document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=37417>Question 37417</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The Graphs of ax+by=13 and ax-by=-3 instersect at (1,4). Find a and b. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #23074 by </B><A HREF=/tutors/aboutme.mpl?userid=ilana><B>ilana(307)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ilana><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=23074\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Both of these equations are true when x=1 and y=4.  So a+4b=13 and a-4b=-3.<BR>\n" );
document.write( "By the second equation, a=4b-3, so we can use that in the first and get (4b-3)+4b=13<BR>\n" );
document.write( "8b-3=13<BR>\n" );
document.write( "8b=16<BR>\n" );
document.write( "b=2<BR>\n" );
document.write( "a+4b=13, so a+4(2)=13, so a+8=13, so a=5.<BR>\n" );
document.write( "So a=5, b=2. </SPAN>\n" );
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