2/3y+y=80

Solution for 2/3y+y=80 equation:

2/3y+y=80

We move all terms to the left:

2/3y+y-(80)=0


Domain of the equation: 3y!=0

y!=0/3

y!=0

y∈R


We add all the numbers together, and all the variables

y+2/3y-80=0

We multiply all the terms by the denominator


y*3y-80*3y+2=0

Wy multiply elements

3y^2-240y+2=0

a = 3; b = -240; c = +2;
Δ = b2-4ac
Δ = -2402-4·3·2
Δ = 57576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{57576}=\sqrt{4*14394}=\sqrt{4}*\sqrt{14394}=2\sqrt{14394}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-240)-2\sqrt{14394}}{2*3}=\frac{240-2\sqrt{14394}}{6}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-240)+2\sqrt{14394}}{2*3}=\frac{240+2\sqrt{14394}}{6}
$