If one root of the equation $x^2+p x+12=0$ is 4 , while the equation $x^2+p x+q=0$ has equal roots, then the…
If one root of the equation $x^2+p x+12=0$ is 4 , while the equation $x^2+p x+q=0$ has equal roots, then the value of ' $q$ ' is
$\frac{49}{4}$
4
3
12
Solution
Since 4 is one of the root of $x^2+p x+12=0 \Rightarrow 16+4 p+12=0 \Rightarrow p=-7$ and equation $x^2+p x+q=0$ has equal roots
$
\Rightarrow D=49-4 q=0 \Rightarrow q=\frac{49}{4}
$