9x2-54x-144=0

Solution for 9x2-54x-144=0 equation:

9x^2-54x-144=0

a = 9; b = -54; c = -144;
Δ = b2-4ac
Δ = -542-4·9·(-144)
Δ = 8100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{8100}=90$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-54)-90}{2*9}=\frac{-36}{18}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-54)+90}{2*9}=\frac{144}{18}
=8
$