Question

If one root of the quadratic equation $2x^2+kx-6=0$ is $2$, then the value of $k$ is

• A. 1
• B. -1
• C. 0
• D. -2

Answer 1

The correct option is B

-1

Find the value of $k$.

Since, the roots of a quadratic polynomial satisfy the polynomial.

$$\begin{gathered} \Rightarrow 2{\left(2\right)}^2+k\left(2\right)-6=0 \\ \Rightarrow 8+2k-6=0 \\ \Rightarrow 2k=-2 \\ \Rightarrow k=-1 \end{gathered}$$

Hence, option $\left(\mathrm{B}\right)$ is correct.