g2=3.15

Solution for g2=3.15 equation:

g2=3.15

We move all terms to the left:

g2-(3.15)=0

We add all the numbers together, and all the variables

g^2-3.15=0

a = 1; b = 0; c = -3.15;
Δ = b2-4ac
Δ = 02-4·1·(-3.15)
Δ = 12.6
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{12.6}}{2*1}=\frac{0-\sqrt{12.6}}{2}
=-\frac{\sqrt{}}{2}
$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{12.6}}{2*1}=\frac{0+\sqrt{12.6}}{2}
=\frac{\sqrt{}}{2}
$