document.write( "Question 758661: the vertices of a triangle ABC are A(2,1) and B(6,-1) and C(4,11).find the equation of altitude through A of triangle ABC
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Algebra.Com's Answer #461605 by Cromlix(4381)![]() ![]() You can put this solution on YOUR website! Find the gradient of BC \n" ); document.write( "Formula: y2 - y1/x2 - x1 \n" ); document.write( " 11-(-1)/4 - 6 \n" ); document.write( " 12/-2 \n" ); document.write( " -6 \n" ); document.write( "As an altitude is at right angles \n" ); document.write( "to the line it emerges from, the \n" ); document.write( "gradient of the line BC and the \n" ); document.write( "gradient of the altitude will \n" ); document.write( "multiply together to give -1 \n" ); document.write( " m1 x m2 = -1 \n" ); document.write( "So, if the gradient of BC is -6 \n" ); document.write( "then the gradient of the altitude \n" ); document.write( "is 1/6. \n" ); document.write( "Setting up the equation: \n" ); document.write( "Using y - b = m(x - a) with m = 1/6 Coords of A (2,1) \n" ); document.write( " y - 1 = 1/6(x - 2) \n" ); document.write( " y - 1 = 1/6x - 2/6 \n" ); document.write( " y = 1/6x - 2/6 + 6/6 (1) \n" ); document.write( " y = 1/6x + 4/6 \n" ); document.write( "This is the equation but you can \n" ); document.write( "multiply through by 6\r \n" ); document.write( "\n" ); document.write( " 6y = x + 4 \n" ); document.write( "Hope this helps. \n" ); document.write( ":-) \n" ); document.write( " |