x^2+63x-216=0

Solution for x^2+63x-216=0 equation:

x^2+63x-216=0

a = 1; b = 63; c = -216;
Δ = b2-4ac
Δ = 632-4·1·(-216)
Δ = 4833
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:

$\sqrt{\Delta}=\sqrt{4833}=\sqrt{9*537}=\sqrt{9}*\sqrt{537}=3\sqrt{537}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(63)-3\sqrt{537}}{2*1}=\frac{-63-3\sqrt{537}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(63)+3\sqrt{537}}{2*1}=\frac{-63+3\sqrt{537}}{2}
$