document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1075942>Question 1075942</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the equation of the median-median line for the data.\r<BR>\n" );
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document.write( "My three points are (500, 524), (2071, 782.5), and (5660, 2330) \r<BR>\n" );
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document.write( "Somehow I have come up with the same equation for Line A and Line B, and then again for the median-median line.\r<BR>\n" );
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document.write( "y = 0.35x + 349\r<BR>\n" );
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document.write( "Am I doing something incorrectly and if so, what is it?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #690597 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=690597\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Label the three points m1, m2, m3 then<BR>\n" );
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document.write( "m1 is (500, 524), m2 is (2071, 782.5) and m3 is (5660, 2330)<BR>\n" );
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document.write( "start with the slope of the line through m1 and m3<BR>\n" );
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document.write( "slope(m1-m3) = (2330 - 524) / (5660 - 500) = 0.35<BR>\n" );
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document.write( "y(m1-m3) = 524 +(0.35)(x-500) <BR>\n" );
document.write( "y(m1-m3) = 0.35x +349<BR>\n" );
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document.write( "y(m2) = 782.5 +(0.35)(x-2071)<BR>\n" );
document.write( "y(m2) = 0.35x +57.65<BR>\n" );
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document.write( "The median-median line is parallel to y(m1-m3) and y(m2) so it will have the same slope(0.35).<BR>\n" );
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document.write( "To find the y-intercept of the median-median line, we find the mean of the y-intercepts of the lines through M1, M2, and M3.  Since there is one line that passes through M1 and M3, the y-intercept for these lines are both 349.  The y-intercept of the line through M2 is 57.65.<BR>\n" );
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document.write( "The mean of the y-intercepts is (349 +349 +57.65) / 3 = 251.8833<BR>\n" );
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document.write( "y(median-median) = 0.35x +251.8833<BR>\n" );
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