2/z-1/5z=-3/20

Solution for 2/z-1/5z=-3/20 equation:

2/z-1/5z=-3/20

We move all terms to the left:

2/z-1/5z-(-3/20)=0


Domain of the equation: z!=0

z∈R



Domain of the equation: 5z!=0

z!=0/5

z!=0

z∈R


We get rid of parentheses

2/z-1/5z+3/20=0

We calculate fractions


75z^2/200z^2+400z/200z^2+(-40z)/200z^2=0

We multiply all the terms by the denominator


75z^2+400z+(-40z)=0

We get rid of parentheses

75z^2+400z-40z=0

We add all the numbers together, and all the variables

75z^2+360z=0

a = 75; b = 360; c = 0;
Δ = b2-4ac
Δ = 3602-4·75·0
Δ = 129600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{129600}=360$
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(360)-360}{2*75}=\frac{-720}{150}
=-4+4/5
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(360)+360}{2*75}=\frac{0}{150}
=0
$