y^2+y=2.2

Solution for y^2+y=2.2 equation:

y^2+y=2.2

We move all terms to the left:

y^2+y-(2.2)=0

We add all the numbers together, and all the variables

y^2+y-2.2=0

a = 1; b = 1; c = -2.2;
Δ = b2-4ac
Δ = 12-4·1·(-2.2)
Δ = 9.8
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{-(1)-\sqrt{9.8}}{2*1}=\frac{-1-\sqrt{9.8}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{9.8}}{2*1}=\frac{-1+\sqrt{9.8}}{2}
$