3a^2+4+13a=0

Solution for 3a^2+4+13a=0 equation:

3a^2+4+13a=0

a = 3; b = 13; c = +4;
Δ = b2-4ac
Δ = 132-4·3·4
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(13)-11}{2*3}=\frac{-24}{6}
=-4
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13)+11}{2*3}=\frac{-2}{6}
=-1/3
$