15g=-9-4g^2

Solution for 15g=-9-4g^2 equation:

15g=-9-4g^2

We move all terms to the left:

15g-(-9-4g^2)=0

We get rid of parentheses

4g^2+15g+9=0

a = 4; b = 15; c = +9;
Δ = b2-4ac
Δ = 152-4·4·9
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-9}{2*4}=\frac{-24}{8}
=-3
$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+9}{2*4}=\frac{-6}{8}
=-3/4
$