document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30599>Question 30599</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how do you solve sytems of equations by graphing? here is an example that my math book gives me: y=2x+4 I have so much trouble tryng to solve these.<BR>\n" );
document.write( "                       x+y=-2.\r<BR>\n" );
document.write( "\n" );
document.write( "I also have trouble tyring to use substitution to solve problems such as this:<BR>\n" );
document.write( "      y=2x-3 Please help me my math grade is going down drastically!!!!!!!<BR>\n" );
document.write( "      y=0<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 #17305 by </B><A HREF=/tutors/aboutme.mpl?userid=Cintchr><B>Cintchr(481)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cintchr><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=17305\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y=2x%2B4+ ALIGN=MIDDLE  ALT=\"+y=2x%2B4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%2By=-2+ ALIGN=MIDDLE  ALT=\"+x%2By=-2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The first equation is in the proper form.  Lets get the 2nd one in that form, too.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1x%2B1y=-2+ ALIGN=MIDDLE  ALT=\"+1x%2B1y=-2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > solve for y<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1y=-1x-2+ ALIGN=MIDDLE  ALT=\"+1y=-1x-2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Let's look at both equations.  They are in y=mx+b format.<BR>\n" );
document.write( "the b is the y-intercept<BR>\n" );
document.write( "the m is the slope (rise/run)<BR>\n" );
document.write( "equation #1 has a y-inter. of +4 and a slope of 2/1<BR>\n" );
document.write( "equation #1 has a y-inter. of -2 and a slope of -1/1<BR>\n" );
document.write( "to plot the first ...<BR>\n" );
document.write( "start at the origin and go up to +4.<BR>\n" );
document.write( "place a dot here at (0,4)<BR>\n" );
document.write( "from here go up 2 and right 1 (rise/run) place another dot.<BR>\n" );
document.write( "Go back to (0,4)<BR>\n" );
document.write( "go down 2 and back 1 and place another dot.<BR>\n" );
document.write( "connect these three points.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+2x%2B4+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+2x%2B4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "now for the second line.<BR>\n" );
document.write( "starting at the origin, go down 2 and place a point (0, -2)<BR>\n" );
document.write( "from here go down one and to the right one.  Place a dot here.<BR>\n" );
document.write( "go back to (0, -2)<BR>\n" );
document.write( "go up one and left one.<BR>\n" );
document.write( "place a third dot here.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+-1x-2+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+-1x-2+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "continue out the lines so that they cross.  This is the solution for the system<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+-1x-2%2C+2x%2B4+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C+-1x-2%2C+2x%2B4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "now for substitution:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y=2x-3+ ALIGN=MIDDLE  ALT=\"+y=2x-3+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y=0+ ALIGN=MIDDLE  ALT=\"+y=0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "the second equation tells you what to put in place of y in the first equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0=2x-3+ ALIGN=MIDDLE  ALT=\"+0=2x-3+\"   DISABLED_style= \"max-width:90%; height:auto;\" > solve for x<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3+=+2x+ ALIGN=MIDDLE  ALT=\"+3+=+2x+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3%2F2+=+x+ ALIGN=MIDDLE  ALT=\"+3%2F2+=+x+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "your ordered pair (solution) is (x, y)<BR>\n" );
document.write( "(3/2, 0) </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );