F(x)=9x^2-3

Solution for F(x)=9x^2-3 equation:

(F)=9F^2-3

We move all terms to the left:

(F)-(9F^2-3)=0

We get rid of parentheses

-9F^2+F+3=0

a = -9; b = 1; c = +3;
Δ = b2-4ac
Δ = 12-4·(-9)·3
Δ = 109
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-\sqrt{109}}{2*-9}=\frac{-1-\sqrt{109}}{-18}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{109}}{2*-9}=\frac{-1+\sqrt{109}}{-18}
$