document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=816364>Question 816364</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine whether triangle QRS is a right triangle for the given vertices. Explain.\r<BR>\n" );
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document.write( "Q(–13, –1), R(–15, –1), S(4, 9)\r<BR>\n" );
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document.write( "please help as soon as possible ! It would be greatly appreciated, thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #491526 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=491526\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28300%2C300%2C-18%2C7%2C-10%2C15%2C%0D%0Agrid%280%29%2C%0D%0Atriangle%28-13%2C-1%2C-15%2C-1%2C4%2C9%29%2C%0D%0Alocate%28-12%2C-1.5%2CQ%29%2Clocate%28-16%2C-1.5%2CR%29%2Clocate%284%2C10.5%2CS%29%0D%0A%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "QR is part of the horizontal line <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-1 ALIGN=MIDDLE  ALT=\"y=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "If QS were a vertical line, the x-coordinate of S would be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-13 ALIGN=MIDDLE  ALT=\"-13\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "just like for Q.<BR>\n" );
document.write( "If RS were vertical, the x-coordinate for S would be :<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-15 ALIGN=MIDDLE  ALT=\"-15\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "Neither QS nor RS are vertical lines,<BR>\n" );
document.write( "so there is no right angle at Q or at R.<BR>\n" );
document.write( "Is there a right angle at S?<BR>\n" );
document.write( "Without calculating, we see that the length of QR is 2 units,<BR>\n" );
document.write( "while QS and RS are much longer, <BR>\n" );
document.write( "So the angle at S is the smallest angle, and cannot be a right angle.<BR>\n" );
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document.write( "NOTES:<BR>\n" );
document.write( "Maybe that was not the way your teacher expects you to get to the answer,<BR>\n" );
document.write( "but it is the shortest way to the answer.<BR>\n" );
document.write( "Maybe there is a typo,<BR>\n" );
document.write( "and I just gave you the right answer to the wrong problem. </SPAN>\n" );
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