F(x)=7x/x-3

Solution for F(x)=7x/x-3 equation:

(F)=7F/F-3

We move all terms to the left:

(F)-(7F/F-3)=0


Domain of the equation: F-3)!=0

F∈R


We get rid of parentheses

F-7F/F+3=0

We multiply all the terms by the denominator


F*F-7F+3*F=0

We add all the numbers together, and all the variables

-4F+F*F=0

Wy multiply elements

F^2-4F=0

a = 1; b = -4; c = 0;
Δ = b2-4ac
Δ = -42-4·1·0
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-4}{2*1}=\frac{0}{2}
=0
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+4}{2*1}=\frac{8}{2}
=4
$