F(x)=2/7x+3

Solution for F(x)=2/7x+3 equation:

(F)=2/7F+3

We move all terms to the left:

(F)-(2/7F+3)=0


Domain of the equation: 7F+3)!=0

F∈R


We get rid of parentheses

F-2/7F-3=0

We multiply all the terms by the denominator


F*7F-3*7F-2=0

Wy multiply elements

7F^2-21F-2=0

a = 7; b = -21; c = -2;
Δ = b2-4ac
Δ = -212-4·7·(-2)
Δ = 497
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{-(-21)-\sqrt{497}}{2*7}=\frac{21-\sqrt{497}}{14}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-21)+\sqrt{497}}{2*7}=\frac{21+\sqrt{497}}{14}
$