F(x)=-56x2+800x+30000

Solution for F(x)=-56x2+800x+30000 equation:

(F)=-56F^2+800F+30000

We move all terms to the left:

(F)-(-56F^2+800F+30000)=0

We get rid of parentheses

56F^2-800F+F-30000=0

We add all the numbers together, and all the variables

56F^2-799F-30000=0

a = 56; b = -799; c = -30000;
Δ = b2-4ac
Δ = -7992-4·56·(-30000)
Δ = 7358401
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{-(-799)-\sqrt{7358401}}{2*56}=\frac{799-\sqrt{7358401}}{112}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-799)+\sqrt{7358401}}{2*56}=\frac{799+\sqrt{7358401}}{112}
$