document.write( "Question 741263: show that the pionts A(1,-1), B(4,-2) and C(16,1) are collinear \n" ); document.write( "
Algebra.Com's Answer #451932 by MathLover1(20850)\"\" \"About 
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if the points A(\"1\",\"-1\"), B(\"4\",\"-2\") and C(\"16\",\"1\") are collinear, they will lie in a straight line;\r
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\n" ); document.write( "\n" ); document.write( "in order to prove the \"3\" points to lie on a line, as there exists a \"unique\" line containing three points and every line has a \"unique\" slope}}}\r
\n" ); document.write( "\n" ); document.write( "Hence it will be sufficient to prove that the slope calculated taking \"2+\" points at a time should be equal.\r
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\n" ); document.write( "\n" ); document.write( "Slope of line taking points (x1,y1)= (\"1\",\"-1\") and (x2,y2)=(\"4\",\"-2\") is\r
\n" ); document.write( "\n" ); document.write( "\"slope=%28y2-y1%29%2F%28x2-x1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=%28-2-%28-1%29%29%2F%284-1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=%28-2%2B1%29%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=-1%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=-0.333\"\r
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\n" ); document.write( "\n" ); document.write( "Slope of line taking points (x1,y1)= (\"1\",\"-1\") and (x2,y2)=(\"16\",\"1\") is\r
\n" ); document.write( "\n" ); document.write( "\"slope=%28y2-y1%29%2F%28x2-x1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=%281-%28-1%29%29%2F%2816-1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=%281%2B1%29%2F15\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=2%2F15\"\r
\n" ); document.write( "\n" ); document.write( "\"slope=0.133\"\r
\n" ); document.write( "\n" ); document.write( "since \"-0.333%3C%3E0.133\", given points are NOT collinear\r
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