(y+2)(y-6)=0y=

Solution for (y+2)(y-6)=0y= equation:

(y+2)(y-6)=0y=

We move all terms to the left:

(y+2)(y-6)-(0y)=0

We add all the numbers together, and all the variables

-1y+(y+2)(y-6)=0

We multiply parentheses ..

(+y^2-6y+2y-12)-1y=0

We get rid of parentheses

y^2-6y+2y-1y-12=0

We add all the numbers together, and all the variables

y^2-5y-12=0

a = 1; b = -5; c = -12;
Δ = b2-4ac
Δ = -52-4·1·(-12)
Δ = 73
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-\sqrt{73}}{2*1}=\frac{5-\sqrt{73}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+\sqrt{73}}{2*1}=\frac{5+\sqrt{73}}{2}
$