4=-5n+6n2

Solution for 4=-5n+6n2 equation:

4=-5n+6n^2

We move all terms to the left:

4-(-5n+6n^2)=0

We get rid of parentheses

-6n^2+5n+4=0

a = -6; b = 5; c = +4;
Δ = b2-4ac
Δ = 52-4·(-6)·4
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(5)-11}{2*-6}=\frac{-16}{-12}
=1+1/3
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+11}{2*-6}=\frac{6}{-12}
=-1/2
$