document.write( "Question 767452: Dear Sir/Madam,
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document.write( "Good day! Kindly help me on this problem:
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document.write( "Find the value of k so that the equation 3x^2-4kx+k = 0 will have real roots. Thank you very much for your help! \n" );
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Algebra.Com's Answer #467627 by lwsshak3(11628)![]() ![]() ![]() You can put this solution on YOUR website! Find the value of k so that the equation 3x^2-4kx+k = 0 will have real roots. \n" ); document.write( "*** \n" ); document.write( "Equation will have 2 equal real roots when the discriminant=0 \n" ); document.write( "a=3, b=-4k, c=k \n" ); document.write( "discriminant=b^2-4*a*c=(-4k)^2-4*3*k=16k^2-12k=0 \n" ); document.write( "k(16k-12)=0 \n" ); document.write( "k=0 (reject) \n" ); document.write( "k=12/16=3/4 \n" ); document.write( ".. \n" ); document.write( "solve for x with k=3/4 \n" ); document.write( "3x^2-4kx+k=3x^2-3x+3/4=0 \n" ); document.write( "12x^2-12x+3=0 \n" ); document.write( "solve for x by quadratic formula: \n" ); document.write( " \n" ); document.write( "a=12, b=-12, c=3 \n" ); document.write( "ans: \n" ); document.write( "x=0.5 (multiplicity 2) \n" ); document.write( " \n" ); document.write( " |