document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136435>Question 136435</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find an equation of the line containing the given pair of points.<BR>\n" );
document.write( "(-3, -2) and (-7, -1)<BR>\n" );
document.write( "The equation of line y is?<BR>\n" );
document.write( "Help please. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99957 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=99957\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can start with the slope-intercept form of a linear equation: <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+mx%2Bb ALIGN=MIDDLE  ALT=\"y+=+mx%2Bb\"   DISABLED_style= \"max-width:90%; height:auto;\" > where m is the slope and b is the y-intercept.<BR>\n" );
document.write( " Let's find the slope, m, using the slope formula:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 ALIGN=MIDDLE  ALT=\"m+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > The x's and y's are taken from the two given points: (-3, -2) = (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B1%5D ALIGN=MIDDLE  ALT=\"x%5B1%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%5B1%5D ALIGN=MIDDLE  ALT=\"y%5B1%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >) and (-7, -1) = (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B2%5D ALIGN=MIDDLE  ALT=\"x%5B2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%5B2%5D ALIGN=MIDDLE  ALT=\"y%5B2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >) So, making the appropriate substitution, we get:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28-1-%28-2%29%29%2F%28-7-%28-3%29%29 ALIGN=MIDDLE  ALT=\"m+=+%28-1-%28-2%29%29%2F%28-7-%28-3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplifying,...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+-%281%2F4%29 ALIGN=MIDDLE  ALT=\"m+=+-%281%2F4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So you can start your equation with:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+%28-1%2F4%29x%2Bb ALIGN=MIDDLE  ALT=\"y+=+%28-1%2F4%29x%2Bb\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now you need to find the value of b, the y-intercept.<BR>\n" );
document.write( "You can do this by substituting the x- and y-coordinate from either of the two given points into the equation above and solving for b.  Let's use the first point (-3, -2) for the x and y.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2+=+%28-1%2F4%29%28-3%29%2Bb ALIGN=MIDDLE  ALT=\"-2+=+%28-1%2F4%29%28-3%29%2Bb\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2+=+%283%2F4%29%2Bb ALIGN=MIDDLE  ALT=\"-2+=+%283%2F4%29%2Bb\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2F4 ALIGN=MIDDLE  ALT=\"3%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > from both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-11%2F4+=+b ALIGN=MIDDLE  ALT=\"-11%2F4+=+b\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now you can write the final equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+%28-1%2F4%29x-11%2F4 ALIGN=MIDDLE  ALT=\"y+=+%28-1%2F4%29x-11%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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