document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1031395>Question 1031395</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Are these 3 points the vertices of a right triangle (-9,5), (-7,9), (-5,8).<BR>\n" );
document.write( "I answered no but not sure if I am doing it right.<BR>\n" );
document.write( "Also are these 3 points Collinear  (-7,0), (-2,4), (-11,-5)<BR>\n" );
document.write( "I answered no on that one also.<BR>\n" );
document.write( "Can you explain how you got your answer so I know how to do it please. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #646105 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=646105\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let the points be P(-9,5), Q(-7,9), R(-5,8).\r<BR>\n" );
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document.write( "==> Line PQ has slope <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5BPQ%5D+=+%289-5%29%2F%28-7%2B9%29+=+4%2F2+=+2 ALIGN=MIDDLE  ALT=\"m%5BPQ%5D+=+%289-5%29%2F%28-7%2B9%29+=+4%2F2+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Line QR has slope <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5BQR%5D+=+%288-9%29%2F%28-5%2B7%29+=+-1%2F2 ALIGN=MIDDLE  ALT=\"m%5BQR%5D+=+%288-9%29%2F%28-5%2B7%29+=+-1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and line PR has slope <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5BPR%5D+=+3%2F4 ALIGN=MIDDLE  ALT=\"m%5BPR%5D+=+3%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Sonce <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%5BPQ%5D%2Am%5BQR%5D+=+-1 ALIGN=MIDDLE  ALT=\"m%5BPQ%5D%2Am%5BQR%5D+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, it follows that line PQ is perpendicular to line QR, and the vertices form a right triangle.\r<BR>\n" );
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document.write( "As for the points (-7,0), (-2,4), (-11,-5), they are NOT collinear, because the area of the triangle formed by these points is not equal to 0.  (If so, they would be collinear.)\r<BR>\n" );
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document.write( "Area = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29abs%28abs+%28matrix%283%2C3%2C1%2C+-7%2C0%2C1%2C+-2%2C4%2C1%2C-11%2C+-5%29%29%29+=+9%2F2+%3C%3E0 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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