(17+y)y=89

Solution for (17+y)y=89 equation:

(17+y)y=89

We move all terms to the left:

(17+y)y-(89)=0

We add all the numbers together, and all the variables

(y+17)y-89=0

We multiply parentheses

y^2+17y-89=0

a = 1; b = 17; c = -89;
Δ = b2-4ac
Δ = 172-4·1·(-89)
Δ = 645
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{-(17)-\sqrt{645}}{2*1}=\frac{-17-\sqrt{645}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+\sqrt{645}}{2*1}=\frac{-17+\sqrt{645}}{2}
$