0.4x^2-36x+450=0

Solution for 0.4x^2-36x+450=0 equation:

0.4x^2-36x+450=0

a = 0.4; b = -36; c = +450;
Δ = b2-4ac
Δ = -362-4·0.4·450
Δ = 576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{576}=24$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-36)-24}{2*0.4}=\frac{12}{0.8}
=15
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-36)+24}{2*0.4}=\frac{60}{0.8}
=75
$