-2(y1)=4y(y+2)

Solution for -2(y1)=4y(y+2) equation:

-2(y1)=4y(y+2)

We move all terms to the left:

-2(y1)-(4y(y+2))=0

We add all the numbers together, and all the variables

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


We calculate terms in parentheses: -(4y(y+2)), so:

4y(y+2)

We multiply parentheses

4y^2+8y

Back to the equation:

-(4y^2+8y)


We get rid of parentheses

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

We add all the numbers together, and all the variables

-4y^2-10y=0

a = -4; b = -10; c = 0;
Δ = b2-4ac
Δ = -102-4·(-4)·0
Δ = 100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{100}=10$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-10)-10}{2*-4}=\frac{0}{-8}
=0
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+10}{2*-4}=\frac{20}{-8}
=-2+1/2
$