document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1021353>Question 1021353</A>: <I><SPAN STYLE=\"word-break: break-all;\"> http://prntscr.com/a5xl25<BR>\n" );
document.write( "Coordinate geometry.<BR>\n" );
document.write( "So, I know I have to use the distance formula, and the points I need to work with are (-a, 0) & (a,0) and the median of the triangle (0,0) & (0,b).  However, I'm not sure how to simplify these variables in the distance formula. Can you help step by step? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #637124 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=637124\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> midpoint of a line is equal to ((x1+x2)/2,(y1+y1)/2)\r<BR>\n" );
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document.write( "(x1,y1) = -a,0<BR>\n" );
document.write( "(x,y2) = a,0\r<BR>\n" );
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document.write( "midpoint is ((a-a)/2,(0-0)/2 = (0,0)\r<BR>\n" );
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document.write( "the median intersect the horizontal line of the triangle at (0,0).\r<BR>\n" );
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document.write( "the slope of the horizontal line is 0.\r<BR>\n" );
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document.write( "slope = (y2-y1) / (x2-x1) = (0-0) / (a-(-a)) = 0 / (2a) = 0.\r<BR>\n" );
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document.write( "the slope of the median is (y2-y1) / (x2-x1) = (b-0) / (0-0) = b/0 = undefined.\r<BR>\n" );
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document.write( "this makes the median a vertical line.\r<BR>\n" );
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document.write( "vertical lines and horizontal lines are perpendicular to each other.\r<BR>\n" );
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document.write( "if the slope is 0, the line is horizontal.\r<BR>\n" );
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document.write( "if the slope is undefined the line is vertical.\r<BR>\n" );
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document.write( "the median is therefore perpendicular to the base of the triangle.\r<BR>\n" );
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