X^2-89x-780=0

Solution for X^2-89x-780=0 equation:

X^2-89X-780=0

a = 1; b = -89; c = -780;
Δ = b2-4ac
Δ = -892-4·1·(-780)
Δ = 11041
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-89)-\sqrt{11041}}{2*1}=\frac{89-\sqrt{11041}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-89)+\sqrt{11041}}{2*1}=\frac{89+\sqrt{11041}}{2}
$