F(x)=2x^2-14x+20

Solution for F(x)=2x^2-14x+20 equation:

(F)=2F^2-14F+20

We move all terms to the left:

(F)-(2F^2-14F+20)=0

We get rid of parentheses

-2F^2+F+14F-20=0

We add all the numbers together, and all the variables

-2F^2+15F-20=0

a = -2; b = 15; c = -20;
Δ = b2-4ac
Δ = 152-4·(-2)·(-20)
Δ = 65
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{-(15)-\sqrt{65}}{2*-2}=\frac{-15-\sqrt{65}}{-4}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+\sqrt{65}}{2*-2}=\frac{-15+\sqrt{65}}{-4}
$