-0.1x2+4.5x-17.5=0

Solution for -0.1x2+4.5x-17.5=0 equation:

-0.1x^2+4.5x-17.5=0

a = -0.1; b = 4.5; c = -17.5;
Δ = b2-4ac
Δ = 4.52-4·(-0.1)·(-17.5)
Δ = 13.25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4.5)-\sqrt{13.25}}{2*-0.1}=\frac{-4.5-\sqrt{13.25}}{-0.2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4.5)+\sqrt{13.25}}{2*-0.1}=\frac{-4.5+\sqrt{13.25}}{-0.2}
$