F(X)=-x2-6x-7

Solution for F(X)=-x2-6x-7 equation:

(F)=-F2-6F-7

We move all terms to the left:

(F)-(-F2-6F-7)=0

We add all the numbers together, and all the variables

-(-1F^2-6F-7)+F=0

We get rid of parentheses

1F^2+6F+F+7=0

We add all the numbers together, and all the variables

F^2+7F+7=0

a = 1; b = 7; c = +7;
Δ = b2-4ac
Δ = 72-4·1·7
Δ = 21
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{-(7)-\sqrt{21}}{2*1}=\frac{-7-\sqrt{21}}{2}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+\sqrt{21}}{2*1}=\frac{-7+\sqrt{21}}{2}
$