y^2-y-8.75=0

Solution for y^2-y-8.75=0 equation:

y^2-y-8.75=0

We add all the numbers together, and all the variables

y^2-1y-8.75=0

a = 1; b = -1; c = -8.75;
Δ = b2-4ac
Δ = -12-4·1·(-8.75)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-6}{2*1}=\frac{-5}{2}
=-2+1/2
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+6}{2*1}=\frac{7}{2}
=3+1/2
$