1/20x+1/30x=15

Solution for 1/20x+1/30x=15 equation:

1/20x+1/30x=15

We move all terms to the left:

1/20x+1/30x-(15)=0


Domain of the equation: 20x!=0

x!=0/20

x!=0

x∈R



Domain of the equation: 30x!=0

x!=0/30

x!=0

x∈R


We calculate fractions


30x/600x^2+20x/600x^2-15=0

We multiply all the terms by the denominator


30x+20x-15*600x^2=0

We add all the numbers together, and all the variables

50x-15*600x^2=0

Wy multiply elements

-9000x^2+50x=0

a = -9000; b = 50; c = 0;
Δ = b2-4ac
Δ = 502-4·(-9000)·0
Δ = 2500
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2500}=50$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(50)-50}{2*-9000}=\frac{-100}{-18000}
=1/180
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(50)+50}{2*-9000}=\frac{0}{-18000}
=0
$