1/5x-1/7x=2

Solution for 1/5x-1/7x=2 equation:

1/5x-1/7x=2

We move all terms to the left:

1/5x-1/7x-(2)=0


Domain of the equation: 5x!=0

x!=0/5

x!=0

x∈R



Domain of the equation: 7x!=0

x!=0/7

x!=0

x∈R


We calculate fractions


7x/35x^2+(-5x)/35x^2-2=0

We multiply all the terms by the denominator


7x+(-5x)-2*35x^2=0

Wy multiply elements

-70x^2+7x+(-5x)=0

We get rid of parentheses

-70x^2+7x-5x=0

We add all the numbers together, and all the variables

-70x^2+2x=0

a = -70; b = 2; c = 0;
Δ = b2-4ac
Δ = 22-4·(-70)·0
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2}{2*-70}=\frac{-4}{-140}
=1/35
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2}{2*-70}=\frac{0}{-140}
=0
$