(4+0.03y)*(2-y)=8

Solution for (4+0.03y)*(2-y)=8 equation:

(4+0.03y)(2-y)=8

We move all terms to the left:

(4+0.03y)(2-y)-(8)=0

We add all the numbers together, and all the variables

(0.03y+4)(-1y+2)-8=0

We multiply parentheses ..

(+0y^2+0y-4y+8)-8=0

We get rid of parentheses

0y^2+0y-4y+8-8=0

We add all the numbers together, and all the variables

y^2-3y=0

a = 1; b = -3; c = 0;
Δ = b2-4ac
Δ = -32-4·1·0
Δ = 9
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9}=3$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-3)-3}{2*1}=\frac{0}{2}
=0
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+3}{2*1}=\frac{6}{2}
=3
$