Question

Solve the equation using the quadratic formula
$2=-\frac{10}{x}-\frac{5}{x^2}$

• A. $\left\{\frac{-5\pm \sqrt{15}}{2}\right\}$
• B. $\left\{\frac{-5\pm \sqrt{15}}{4}\right\}$
• C. $\left\{\frac{-5\pm \sqrt{35}}{2}\right\}$
• D. $\left\{\frac{-10\pm \sqrt{15}}{2}\right\}$

Answer 1

Answer: (A)

$\left\{\frac{-5\pm \sqrt{15}}{2}\right\}$

Given equation $2=-\frac{10}{x}-\frac{5}{x^2}$

$\Rightarrow 2x^2+10x+5=0$.

When this equation is compared with general equation $a{x}^2+bx+c=0$

$a=3$, $b=10$ and $c=5$

Quadratic formula given by sri dharacharya, $x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}.$

On substituting values, we get

$x=\frac{-5\pm \sqrt{15}}{2}.$