# How do you solve the quadratic 10x^2+7=-3 using any method?

Oct 29, 2016

Answer is $x = \pm i = \pm \sqrt{-} 1$.
$10 {x}^{2} + 7 = - 3$
$\therefore 10 {x}^{2} = - 10$
$\therefore {x}^{2} = - 1$
$\therefore {x}^{2} = {i}^{2}$ [ $i$ is imaginary number, $i = \sqrt{-} 1$]
$\therefore x = \pm i$
$\therefore x = \pm \sqrt{-} 1$. (answer).