Question

If one root of the quadratic equation $k{x}^2-7x+12=0$ is $3$, then find the value of $k$.

Answer 1

Given quadratic equation: $k{x}^2-7x+12=0$

If $x=3$ is the root of above equation, then

$k(3{)}^2-7(3)+12=0$

$\Rightarrow 9k-21+12=0$

$\Rightarrow k=1$