-0.2x^2+1.7x+6=0

Solution for -0.2x^2+1.7x+6=0 equation:

-0.2x^2+1.7x+6=0

a = -0.2; b = 1.7; c = +6;
Δ = b2-4ac
Δ = 1.72-4·(-0.2)·6
Δ = 7.69
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{-(1.7)-\sqrt{7.69}}{2*-0.2}=\frac{-1.7-\sqrt{7.69}}{-0.4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.7)+\sqrt{7.69}}{2*-0.2}=\frac{-1.7+\sqrt{7.69}}{-0.4}
$