X^2+56x-204=0

Solution for X^2+56x-204=0 equation:

X^2+56X-204=0

a = 1; b = 56; c = -204;
Δ = b2-4ac
Δ = 562-4·1·(-204)
Δ = 3952
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:

$\sqrt{\Delta}=\sqrt{3952}=\sqrt{16*247}=\sqrt{16}*\sqrt{247}=4\sqrt{247}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(56)-4\sqrt{247}}{2*1}=\frac{-56-4\sqrt{247}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(56)+4\sqrt{247}}{2*1}=\frac{-56+4\sqrt{247}}{2}
$