-0.005x^2+4.5x-6.5=0

Solution for -0.005x^2+4.5x-6.5=0 equation:

-0.005x^2+4.5x-6.5=0

a = -0.005; b = 4.5; c = -6.5;
Δ = b2-4ac
Δ = 4.52-4·(-0.005)·(-6.5)
Δ = 20.12
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{20.12}}{2*-0.005}=\frac{-4.5-\sqrt{20.12}}{-0.01}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4.5)+\sqrt{20.12}}{2*-0.005}=\frac{-4.5+\sqrt{20.12}}{-0.01}
$