40x=8x^2

Solution for 40x=8x^2 equation:

40x=8x^2

We move all terms to the left:

40x-(8x^2)=0

determiningTheFunctionDomain
-8x^2+40x=0

a = -8; b = 40; c = 0;
Δ = b2-4ac
Δ = 402-4·(-8)·0
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(40)-40}{2*-8}=\frac{-80}{-16}
=+5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(40)+40}{2*-8}=\frac{0}{-16}
=0
$