x^2+1.8x-1.2=0

Solution for x^2+1.8x-1.2=0 equation:

x^2+1.8x-1.2=0

a = 1; b = 1.8; c = -1.2;
Δ = b2-4ac
Δ = 1.82-4·1·(-1.2)
Δ = 8.04
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{-(1.8)-\sqrt{8.04}}{2*1}=\frac{-1.8-\sqrt{8.04}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.8)+\sqrt{8.04}}{2*1}=\frac{-1.8+\sqrt{8.04}}{2}
$