9X^2-30x-171=0

Solution for 9X^2-30x-171=0 equation:

9X^2-30X-171=0

a = 9; b = -30; c = -171;
Δ = b2-4ac
Δ = -302-4·9·(-171)
Δ = 7056
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{7056}=84$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-30)-84}{2*9}=\frac{-54}{18}
=-3
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-30)+84}{2*9}=\frac{114}{18}
=6+1/3
$