r^2-19r-2790=0

Solution for r^2-19r-2790=0 equation:

r^2-19r-2790=0

a = 1; b = -19; c = -2790;
Δ = b2-4ac
Δ = -192-4·1·(-2790)
Δ = 11521
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-19)-\sqrt{11521}}{2*1}=\frac{19-\sqrt{11521}}{2}
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-19)+\sqrt{11521}}{2*1}=\frac{19+\sqrt{11521}}{2}
$