0.1x^2-0.7x+1.2=0

Solution for 0.1x^2-0.7x+1.2=0 equation:

0.1x^2-0.7x+1.2=0

a = 0.1; b = -0.7; c = +1.2;
Δ = b2-4ac
Δ = -0.72-4·0.1·1.2
Δ = 0.01
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{-(-0.7)-\sqrt{0.01}}{2*0.1}=\frac{0.7-\sqrt{0.01}}{0.2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.7)+\sqrt{0.01}}{2*0.1}=\frac{0.7+\sqrt{0.01}}{0.2}
$