Question

If x = 3 is one root of the quadratic equation x² – 2kx – 6 = 0, then find the value of k.

Answer 1

If x = 3 is a root of the quadratic equation x² − 2kx ​− 6 = 0, then it will satisfy the given equation.
Put x = 3 in given quadratic equation
⇒ 3² − 2k(3) − 6 = 0
⇒ k = $\frac{1}{2}$