4/5x-2x=3

Solution for 4/5x-2x=3 equation:

4/5x-2x=3

We move all terms to the left:

4/5x-2x-(3)=0


Domain of the equation: 5x!=0

x!=0/5

x!=0

x∈R


We add all the numbers together, and all the variables

-2x+4/5x-3=0

We multiply all the terms by the denominator


-2x*5x-3*5x+4=0

Wy multiply elements

-10x^2-15x+4=0

a = -10; b = -15; c = +4;
Δ = b2-4ac
Δ = -152-4·(-10)·4
Δ = 385
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-\sqrt{385}}{2*-10}=\frac{15-\sqrt{385}}{-20}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+\sqrt{385}}{2*-10}=\frac{15+\sqrt{385}}{-20}
$