document.write( "Question 1160834: Find the point on the line y=5x+1 that is closest to the point (3,5) . \n" ); document.write( "
Algebra.Com's Answer #784266 by ikleyn(52790)\"\" \"About 
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document.write( "On the line (x,5x+1) we want to find the point closest to (3,5).\r\n" );
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document.write( "Write the distance formula (the square of distance formula)\r\n" );
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document.write( "    d^2 = (x-3)^2 + (5x+1-5)^2 = \r\n" );
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document.write( "          (x-3)^2 + (5x-4)^2 = x^2 - 6x + 9 + 25x^2 - 40x + 16 = \r\n" );
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document.write( "                             = 26x^2 - 46x + 25.\r\n" );
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document.write( "The minimum of this quadratic form is at  x = \"-b%2F%282a%29\" = \"46%2F%282%2A26%29\" = \"23%2F26\".\r\n" );
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document.write( "ANSWER.  The closest point is  ( \"23%2F26\",\"5%2A%2824%2F26%29%2B1\" ) = ( \"23%2F26\",\"141%2F26\" ).\r\n" );
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