.001x^2+3.4x-80=0

Solution for .001x^2+3.4x-80=0 equation:

.001x^2+3.4x-80=0

a = .001; b = 3.4; c = -80;
Δ = b2-4ac
Δ = 3.42-4·.001·(-80)
Δ = 11.88
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{-(3.4)-\sqrt{11.88}}{2*.001}=\frac{-3.4-\sqrt{11.88}}{0.002}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3.4)+\sqrt{11.88}}{2*.001}=\frac{-3.4+\sqrt{11.88}}{0.002}
$