4a^2+80=36a

Solution for 4a^2+80=36a equation:

4a^2+80=36a

We move all terms to the left:

4a^2+80-(36a)=0

a = 4; b = -36; c = +80;
Δ = b2-4ac
Δ = -362-4·4·80
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-36)-4}{2*4}=\frac{32}{8}
=4
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-36)+4}{2*4}=\frac{40}{8}
=5
$