9=y2+2y+2y+4

Solution for 9=y2+2y+2y+4 equation:

9=y2+2y+2y+4

We move all terms to the left:

9-(y2+2y+2y+4)=0

We add all the numbers together, and all the variables

-(+y^2+4y+4)+9=0

We get rid of parentheses

-y^2-4y-4+9=0

We add all the numbers together, and all the variables

-1y^2-4y+5=0

a = -1; b = -4; c = +5;
Δ = b2-4ac
Δ = -42-4·(-1)·5
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-6}{2*-1}=\frac{-2}{-2}
=1
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+6}{2*-1}=\frac{10}{-2}
=-5
$