y^2+y=10100

Solution for y^2+y=10100 equation:

y^2+y=10100

We move all terms to the left:

y^2+y-(10100)=0

a = 1; b = 1; c = -10100;
Δ = b2-4ac
Δ = 12-4·1·(-10100)
Δ = 40401
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{40401}=201$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-201}{2*1}=\frac{-202}{2}
=-101
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+201}{2*1}=\frac{200}{2}
=100
$