9x^2-17x-76=0

Solution for 9x^2-17x-76=0 equation:

9x^2-17x-76=0

a = 9; b = -17; c = -76;
Δ = b2-4ac
Δ = -172-4·9·(-76)
Δ = 3025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3025}=55$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-17)-55}{2*9}=\frac{-38}{18}
=-2+1/9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+55}{2*9}=\frac{72}{18}
=4
$