5b^2+4=-12b

Solution for 5b^2+4=-12b equation:

5b^2+4=-12b

We move all terms to the left:

5b^2+4-(-12b)=0

We get rid of parentheses

5b^2+12b+4=0

a = 5; b = 12; c = +4;
Δ = b2-4ac
Δ = 122-4·5·4
Δ = 64
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{64}=8$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-8}{2*5}=\frac{-20}{10}
=-2
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+8}{2*5}=\frac{-4}{10}
=-2/5
$