(3+y)(2y+9)=0

Solution for (3+y)(2y+9)=0 equation:

(3+y)(2y+9)=0

We add all the numbers together, and all the variables

(y+3)(2y+9)=0

We multiply parentheses ..

(+2y^2+9y+6y+27)=0

We get rid of parentheses

2y^2+9y+6y+27=0

We add all the numbers together, and all the variables

2y^2+15y+27=0

a = 2; b = 15; c = +27;
Δ = b2-4ac
Δ = 152-4·2·27
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{-(15)-3}{2*2}=\frac{-18}{4}
=-4+1/2
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+3}{2*2}=\frac{-12}{4}
=-3
$