9n^2+3n-56=0

Solution for 9n^2+3n-56=0 equation:

9n^2+3n-56=0

a = 9; b = 3; c = -56;
Δ = b2-4ac
Δ = 32-4·9·(-56)
Δ = 2025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2025}=45$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-45}{2*9}=\frac{-48}{18}
=-2+2/3
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+45}{2*9}=\frac{42}{18}
=2+1/3
$