-5x^2=-315

Solution for -5x^2=-315 equation:

-5x^2=-315

We move all terms to the left:

-5x^2-(-315)=0

We add all the numbers together, and all the variables

-5x^2+315=0

a = -5; b = 0; c = +315;
Δ = b2-4ac
Δ = 02-4·(-5)·315
Δ = 6300
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{6300}=\sqrt{900*7}=\sqrt{900}*\sqrt{7}=30\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-30\sqrt{7}}{2*-5}=\frac{0-30\sqrt{7}}{-10}
=-\frac{30\sqrt{7}}{-10}
=-\frac{3\sqrt{7}}{-1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+30\sqrt{7}}{2*-5}=\frac{0+30\sqrt{7}}{-10}
=\frac{30\sqrt{7}}{-10}
=\frac{3\sqrt{7}}{-1}
$