document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=249778>Question 249778</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if the points (3, r) and (r, -1) lie on a line with slope -3/4, wat is the value of r?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #181866 by </B><A HREF=/tutors/aboutme.mpl?userid=mathhub><B>mathhub(11)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathhub><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=181866\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The coordinates of two points connecting the line are given. <BR>\n" );
document.write( "Let's say the 2 points are denoted as A and B. Let us assign the coordinates (3, r) topoint A and coordinates (r, -1) to point B.\r<BR>\n" );
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document.write( "The slope of the line is given by the difference of the y-coordinates over the difference of x-coordinates of points A and B.\r<BR>\n" );
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document.write( "Thus the slope is given by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r%2B1%29%2F%283-r%29 ALIGN=MIDDLE  ALT=\"%28r%2B1%29%2F%283-r%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "But then as per the question the slope of the line is -3/4. That means\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r%2B1%29%2F%283-r%29 ALIGN=MIDDLE  ALT=\"%28r%2B1%29%2F%283-r%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <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;\" ><BR>\n" );
document.write( "=> 4(r+1) = -3(3-r)<BR>\n" );
document.write( "=> 4r + 4 = -9 + 3r<BR>\n" );
document.write( "=> 4r - 3r = -9 - 4<BR>\n" );
document.write( "=> r = -13\r<BR>\n" );
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document.write( "Therefore the value of r is -13. </SPAN>\n" );
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