-5y^2+36y-64=0

Solution for -5y^2+36y-64=0 equation:

-5y^2+36y-64=0

a = -5; b = 36; c = -64;
Δ = b2-4ac
Δ = 362-4·(-5)·(-64)
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-4}{2*-5}=\frac{-40}{-10}
=+4
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+4}{2*-5}=\frac{-32}{-10}
=3+1/5
$