F(x)=49x^2-9

Solution for F(x)=49x^2-9 equation:

(F)=49F^2-9

We move all terms to the left:

(F)-(49F^2-9)=0

We get rid of parentheses

-49F^2+F+9=0

a = -49; b = 1; c = +9;
Δ = b2-4ac
Δ = 12-4·(-49)·9
Δ = 1765
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{1765}}{2*-49}=\frac{-1-\sqrt{1765}}{-98}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{1765}}{2*-49}=\frac{-1+\sqrt{1765}}{-98}
$