document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=545238>Question 545238</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the Equation of a Line Given That You Know Two Points it Passes Through.\r<BR>\n" );
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document.write( "(1/2,-3) and (-2,1)\r<BR>\n" );
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document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #355574 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5396)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=355574\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When you know two points in a line, you can calculate the slope. Then, with the slope and just one point, you can write the equation of the line.<BR>\n" );
document.write( "The slope (usually represented by m) can be calculated as the difference in y coordinate, divided by the difference in x coordinate (also called rise and run). So,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m=%28-3-1%29%2F%281%2F2-%28-2%29%29=%28-4%29%2F%281%2F2%2B2%29=%28-4%29%2F%285%2F2%29=-4%2A%282%2F5%29=-8%2F5 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2-%28-2%29%29=5%2F2 ALIGN=MIDDLE  ALT=\"%281%2F2-%28-2%29%29=5%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the run, the increase in x as you go from (-2,1) to (1/2,-3)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3-1=-4 ALIGN=MIDDLE  ALT=\"-3-1=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the rise, how much y rises as you go from (-2,1) to (1/2,-3), and you know that it goes down by 4, so the rise is -4.<BR>\n" );
document.write( "With the slope (m) and one point (h,k), you can write the equation of the line in the point-slope form as<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y-k=m%28x-h%29 ALIGN=MIDDLE  ALT=\"y-k=m%28x-h%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So, using point (-2,1),<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y-1=-%288%2F5%29%28x-%28-2%29%29 ALIGN=MIDDLE  ALT=\"y-1=-%288%2F5%29%28x-%28-2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><--><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y-1=-%288%2F5%29%28x%2B2%29 ALIGN=MIDDLE  ALT=\"y-1=-%288%2F5%29%28x%2B2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "And we can transform that equation into the slope-intercept form like this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-%288%2F5%29x-16%2F5%2B1 ALIGN=MIDDLE  ALT=\"y=-%288%2F5%29x-16%2F5%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><--><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-%288%2F5%29x-11%2F5 ALIGN=MIDDLE  ALT=\"y=-%288%2F5%29x-11%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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