1/4x+1/5x=3/20

Solution for 1/4x+1/5x=3/20 equation:

1/4x+1/5x=3/20

We move all terms to the left:

1/4x+1/5x-(3/20)=0


Domain of the equation: 4x!=0

x!=0/4

x!=0

x∈R



Domain of the equation: 5x!=0

x!=0/5

x!=0

x∈R


We add all the numbers together, and all the variables

1/4x+1/5x-(+3/20)=0

We get rid of parentheses

1/4x+1/5x-3/20=0

We calculate fractions


(-300x^2)/800x^2+200x/800x^2+160x/800x^2=0

We multiply all the terms by the denominator


(-300x^2)+200x+160x=0

We add all the numbers together, and all the variables

(-300x^2)+360x=0

We get rid of parentheses

-300x^2+360x=0

a = -300; b = 360; c = 0;
Δ = b2-4ac
Δ = 3602-4·(-300)·0
Δ = 129600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{129600}=360$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(360)-360}{2*-300}=\frac{-720}{-600}
=1+1/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(360)+360}{2*-300}=\frac{0}{-600}
=0
$