y^2-y-900=0

Solution for y^2-y-900=0 equation:

y^2-y-900=0

We add all the numbers together, and all the variables

y^2-1y-900=0

a = 1; b = -1; c = -900;
Δ = b2-4ac
Δ = -12-4·1·(-900)
Δ = 3601
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{3601}}{2*1}=\frac{1-\sqrt{3601}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{3601}}{2*1}=\frac{1+\sqrt{3601}}{2}
$