document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=4887>Question 4887</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the equation of each line. Write the answer in standard form using only integers.\r<BR>\n" );
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document.write( "The problem is:\r<BR>\n" );
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document.write( "The line through the points (-1,-3) and (2, -1).\r<BR>\n" );
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document.write( "Please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #2381 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=2381\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> find the gradient, m:\r<BR>\n" );
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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;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28%28-3%29-%28-1%29%29%2F%28%28-1%29-%282%29%29 ALIGN=MIDDLE  ALT=\"m+=+%28%28-3%29-%28-1%29%29%2F%28%28-1%29-%282%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28-3%2B1%29%2F%28-1-2%29 ALIGN=MIDDLE  ALT=\"m+=+%28-3%2B1%29%2F%28-1-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28-2%29%2F%28-3%29 ALIGN=MIDDLE  ALT=\"m+=+%28-2%29%2F%28-3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "m = 2/3\r<BR>\n" );
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document.write( "So, y=mx+c, we now have y=(2/3)x+c\r<BR>\n" );
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document.write( "Put in one of the coordinate pairs now, to find c - either, it doesn't matter. I will pick (2,-1).\r<BR>\n" );
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document.write( "-1 = (2/3)(2) + c<BR>\n" );
document.write( "-1 = 4/3 + c<BR>\n" );
document.write( "c = -1 - 4/3<BR>\n" );
document.write( "c = -3/3 - 4/3<BR>\n" );
document.write( "c = -7/3\r<BR>\n" );
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document.write( "so equation is y = (2/3)x - 7/3, but the Q wants everything in integers, not fractions, so...multiply all terms by 3 to give 3y = 2x - 7. Done!\r<BR>\n" );
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document.write( "To be safe, use the other coordinates that you did not use...put the x value into thet equation and see if you get y=-3 out. If you do, your equation is correct. If not, you have calcualted something wrong somewhere, so you can check your working.\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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