Question

If x is equals to 3 is 1 root of quadratic equation X square - 2kx - 6 =0 then find the value of k

Answer 1

we know that 3 is one factor hence take x = 3

substituting values we get

9 - 6k - 6 = 0
3 - 6k = 0
3 = 6k
hence k = 1/2 

hope it helped :-)