F(x)=-5x^2+50

Solution for F(x)=-5x^2+50 equation:

(F)=-5F^2+50

We move all terms to the left:

(F)-(-5F^2+50)=0

We get rid of parentheses

5F^2+F-50=0

a = 5; b = 1; c = -50;
Δ = b2-4ac
Δ = 12-4·5·(-50)
Δ = 1001
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{1001}}{2*5}=\frac{-1-\sqrt{1001}}{10}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{1001}}{2*5}=\frac{-1+\sqrt{1001}}{10}
$