For what values of k are the roots of the quadratic equation 3xsq +2kx

1.	For what values of k are the roots of the quadratic equation 3xsq +2kx+27=0 real and equal
Answer» We have the following equation,3x2\xa0- 2kx + 27\xa0= 0a = 3, b = -2k\xa0and c = 27{tex}\\therefore{/tex}\xa0D = b2\xa0- 4ac= (-2k)2\xa0- 4(3)(27)= 4k2 - 324Roots are real and equal if D = 0{tex}\\Rightarrow{/tex}\xa04k2\xa0- 324 = 0k\u200b\u200b\u200b\u200b\u200b\u200b2=\xa0{tex}\\frac { 324 } { 4 }{/tex} = 81{tex}\\therefore k = \\pm 9{/tex}

Discussion