document.write( "Question 865629: One of the roots of the equation y= -2x^2+kx+(k+2) is located at x=3
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document.write( "A) determine the value of k
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document.write( "B) determine the other root of this equation \n" );
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Algebra.Com's Answer #521797 by htmentor(1343)![]() ![]() You can put this solution on YOUR website! One of the roots of the equation y= -2x^2+kx+(k+2) is located at x=3 \n" ); document.write( "A) determine the value of k \n" ); document.write( "B) determine the other root of this equation\r \n" ); document.write( "\n" ); document.write( "To determine k, we substitute x=3 into the equation -2x^2 + kx + (k+2) = 0 \n" ); document.write( "This gives -2(3)^2 + 3k + k + 2 = 0 \n" ); document.write( "Solving for k gives k=4 \n" ); document.write( "So the equation is y = -2x^2 + 4x + 6 \n" ); document.write( "To get the other root, we know that one of the factors of this quadratic is x-3. \n" ); document.write( "From this we can determine the other factor: \n" ); document.write( "(x-3)(-2x-2) = 0 \n" ); document.write( "This gives x=-1\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |