document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=956398>Question 956398</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is the relationship shown by the data below linear? If so, model the data with an equation.\r<BR>\n" );
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document.write( "x: -11,-1,4,19<BR>\n" );
document.write( "y: -7,-3,-1,5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #584304 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=584304\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> slopw = (y2 - y1) / (x2 - x1)\r<BR>\n" );
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document.write( "the slope from all the points is equal to 2/5.\r<BR>\n" );
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document.write( "the data can be modeled by a linear equation.\r<BR>\n" );
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document.write( "take any two of the points and model the linear equation.\r<BR>\n" );
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document.write( "choose (x1,y1) = (-11,-7)<BR>\n" );
document.write( "choose (x2,y2) = 19,5)\r<BR>\n" );
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document.write( "slope = (5--7)/(19--11) = (5+7)/(19+11) = 12/30 = 2/5.\r<BR>\n" );
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document.write( "use any one of the points on the line to find the equation.\r<BR>\n" );
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document.write( "slope intercept form is y = mx + b.<BR>\n" );
document.write( "m = 2/5<BR>\n" );
document.write( "y = -11<BR>\n" );
document.write( "x = 19<BR>\n" );
document.write( "equation becomes:<BR>\n" );
document.write( "5 = 2/5 * 19 + b<BR>\n" );
document.write( "solve for b to get:<BR>\n" );
document.write( "b = 5 - 2/5 * 19<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "b = 5 - 7.6<BR>\n" );
document.write( "simplify further to get:<BR>\n" );
document.write( "b = -2.6<BR>\n" );
document.write( "equation becomes:<BR>\n" );
document.write( "y = 2/5 * x -2.6\r<BR>\n" );
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document.write( "graph of that equation looks like this:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2015/031703.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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