document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=40814>Question 40814</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534493947/algebrahomeworkh>INTERMEDIATE ALGEBRA</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system of equations using the substitution method.<BR>\n" );
document.write( "If the answer is a unique solution, present it as an ordered pair: (x, y).  If not, specify whether the answer is “no solution” or “infinitely many solutions.”<BR>\n" );
document.write( "3x + y = 7<BR>\n" );
document.write( "4x – y = 21<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #26210 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=26210\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3x + y = 7<BR>\n" );
document.write( "4x – y = 21\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Add the two equations to get:<BR>\n" );
document.write( "7x=28<BR>\n" );
document.write( "x=4<BR>\n" );
document.write( "Substitute that value into either of the original equations<BR>\n" );
document.write( "to solve for \"y\".<BR>\n" );
document.write( "3(4)+y=7<BR>\n" );
document.write( "y=-5<BR>\n" );
document.write( "Solution:  x=4, y=-5<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );