0.1x^2-2x+7.5=0

Solution for 0.1x^2-2x+7.5=0 equation:

0.1x^2-2x+7.5=0

a = 0.1; b = -2; c = +7.5;
Δ = b2-4ac
Δ = -22-4·0.1·7.5
Δ = 1
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1}=1$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-1}{2*0.1}=\frac{1}{0.2}
=5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+1}{2*0.1}=\frac{3}{0.2}
=15
$