If one zero of the quadratic polynomial x2 + 3x + k is 2, then find the value of k

 

1.    If one zero of the quadratic polynomial x² + 3x + k is 2, then find the value of k

Soln:

          Given that,

                   P(x)   =        x² + 3x + k

          Also given that 2 is one of the zero of p(x)

          i.e., p(2)     =        0

                   2² + 3x2 + k         = 0

                   4 + 6 + k              = 0

                   10 + k                  = 0

                   k                           = -10

Hence the value of ‘k’ is  -10 .