4y-(80/y)=4

Solution for 4y-(80/y)=4 equation:

4y-(80/y)=4

We move all terms to the left:

4y-(80/y)-(4)=0


Domain of the equation: y)!=0

y!=0/1

y!=0

y∈R


We add all the numbers together, and all the variables

4y-(+80/y)-4=0

We get rid of parentheses

4y-80/y-4=0

We multiply all the terms by the denominator


4y*y-4*y-80=0

We add all the numbers together, and all the variables

-4y+4y*y-80=0

Wy multiply elements

4y^2-4y-80=0

a = 4; b = -4; c = -80;
Δ = b2-4ac
Δ = -42-4·4·(-80)
Δ = 1296
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1296}=36$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-36}{2*4}=\frac{-32}{8}
=-4
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+36}{2*4}=\frac{40}{8}
=5
$