Question

The sum of the roots and the product of roots of a quadratic equation $3x^2-(2K+1)x-K-5=0$ are equal. The value of $K$ will be

• A. $-\frac{1}{2}$
• B. $-2$
• C. $\frac{1}{2}$
• D. $5$

Answer 1

The correct option is B $-2$

Given equation is: $3x^2-(2K+1)x-K-5=0$

The sum of the roots of the equations $=\frac{2k+1}{3}$
And the products of the roots of the equations $=\frac{-k-5}{3}$
$\Rightarrow \frac{2k+1}{3}=\frac{-k-5}{3}$
$\Rightarrow 2k+1=-k-5$
$\Rightarrow 3k=-6$
$\Rightarrow k=-2$