17x^2-220x-13=0

Solution for 17x^2-220x-13=0 equation:

17x^2-220x-13=0

a = 17; b = -220; c = -13;
Δ = b2-4ac
Δ = -2202-4·17·(-13)
Δ = 49284
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49284}=222$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-220)-222}{2*17}=\frac{-2}{34}
=-1/17
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-220)+222}{2*17}=\frac{442}{34}
=13
$