document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=83475>Question 83475</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I know I need to use substitution to solve the system, but can you help me here.<BR>\n" );
document.write( "4x-4y=-8<BR>\n" );
document.write( "y=2+x<BR>\n" );
document.write( "please solve </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #60001 by </B><A HREF=/tutors/aboutme.mpl?userid=funmath><B>funmath(2933)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=funmath><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=60001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use substitution to solve the system:<BR>\n" );
document.write( "4x-4y=-8<BR>\n" );
document.write( "y=2+x<BR>\n" );
document.write( "Let y=2+x in the first equation:<BR>\n" );
document.write( "4x-4(2+x)=-8<BR>\n" );
document.write( "4x-8-4x=-8<BR>\n" );
document.write( "-8=-8<BR>\n" );
document.write( "Because the variable was eliminated and -8=-8 this is a dependent system, the solution is all real numbers because algebraically no matter what number we let x = they will both have the same y.  Graphically these are two lines lying on top of each other having all points in common.<BR>\n" );
document.write( "Some teachers let you say the solution is ALL REAL NUMBERS<BR>\n" );
document.write( "Others prefer coordinate notation (x,y)=(x,2+x)<BR>\n" );
document.write( "Happy Calculating!!!<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );