y(y+7)=330

Solution for y(y+7)=330 equation:

y(y+7)=330

We move all terms to the left:

y(y+7)-(330)=0

We multiply parentheses

y^2+7y-330=0

a = 1; b = 7; c = -330;
Δ = b2-4ac
Δ = 72-4·1·(-330)
Δ = 1369
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1369}=37$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-37}{2*1}=\frac{-44}{2}
=-22
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+37}{2*1}=\frac{30}{2}
=15
$