-3u^2-20u+63=0

Solution for -3u^2-20u+63=0 equation:

-3u^2-20u+63=0

a = -3; b = -20; c = +63;
Δ = b2-4ac
Δ = -202-4·(-3)·63
Δ = 1156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1156}=34$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-20)-34}{2*-3}=\frac{-14}{-6}
=2+1/3
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-20)+34}{2*-3}=\frac{54}{-6}
=-9
$