document.write( "Question 1178012: The coordinates of the point P,Q,R are (-1,11),(2,5) and (t,3) respectively. Given that ∠PQR = 90 °, calculate the value of t. The line PQ is produced to S so that QS = PQ. Calculate the coordinates of S. \n" ); document.write( "
Algebra.Com's Answer #807205 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "P,Q,R are (\"-1\" ,\"11\" ),(\"2\" ,\"5\" ) and (\"t\" ,\"3\" ) respectively\r
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\n" ); document.write( "\n" ); document.write( "first find the slope of the line passes through
\n" ); document.write( "P(\"-1\" ,\"11\" ) and Q(\"2\" ,\"5\" )\r
\n" ); document.write( "\n" ); document.write( "\"m=%285-11%29%2F%282-%28-1%29%29=-6%2F3=-2\"\r
\n" ); document.write( "\n" ); document.write( "\"y=-2x%2Bb\"....use one point to calculate \"b\"\r
\n" ); document.write( "\n" ); document.write( "\"5=-2%2A2%2Bb\"\r
\n" ); document.write( "\n" ); document.write( "\"b=5%2B4\"\r
\n" ); document.write( "\n" ); document.write( "\"b=9\"\r
\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B9\".....eq.1\r
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\n" ); document.write( "\n" ); document.write( "since given that ∠\"PQR+=+90\" °, find a line that is perpendicular to line with a slope \"-2\" and passes through Q and R\r
\n" ); document.write( "\n" ); document.write( "\"y=mx%2Bb\"\r
\n" ); document.write( "\n" ); document.write( "the slope of the perpendicular line will be negative reciprocal of the slope \"-2\" and it is\r
\n" ); document.write( "\n" ); document.write( "\"m=-1%2F-2=1%2F2\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x%2Bb\"...use one point to calculate \"b\"
\n" ); document.write( "\"5=%281%2F2%292%2Bb\"
\n" ); document.write( "\"5=1%2Bb\"
\n" ); document.write( "\"b=4\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x%2B4\".....eq.2\r
\n" ); document.write( "\n" ); document.write( "since given (\"t\" ,\"3\" ), we use line\"+y=3\" and the intersection point of the \"y=%281%2F2%29x%2B4\" and \"+y=3\" will have \"x=t\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x%2B4\"...substitute \"+y\"
\n" ); document.write( "\"3=%281%2F2%29x%2B4\"
\n" ); document.write( "\"3-4=%281%2F2%29x\"
\n" ); document.write( "\"-1%2A2=x\"
\n" ); document.write( "\"x=-2\"=>\"t=-2\" and the point \"R\"(\"-2\" ,\"3\" ) \r
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\n" ); document.write( "\n" ); document.write( "given also: the line\"+PQ\" is produced to \"S\" so that \"QS+=+PQ\". Calculate the coordinates of \"S\".\r
\n" ); document.write( "\n" ); document.write( "\"S\" will be on a line \"y=%281%2F2%29x%2B4\", from \"Q\" same distance as \"+PQ\"\r
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\n" ); document.write( "\n" ); document.write( "\"d=sqrt%28%282-%28-1%29%29%5E2%2B%285-11%29%5E2%29\"
\n" ); document.write( "\"d=sqrt%283%5E2%2B%28-6%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "distance is \"d=sqrt%2845%29=6.7\" which is radius \"r\" of the circle that passes through P, Q, and S\r
\n" ); document.write( "\n" ); document.write( "use the radius , draw a circle and read from the graph what are the coordinates of the point S\r
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\n" ); document.write( "\n" ); document.write( " \r
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\n" ); document.write( "\n" ); document.write( "\"S\"(\"-4\" ,\"2\" ) \r
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