x^2+1.4x-1=0

Solution for x^2+1.4x-1=0 equation:

x^2+1.4x-1=0

a = 1; b = 1.4; c = -1;
Δ = b2-4ac
Δ = 1.42-4·1·(-1)
Δ = 5.96
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{-(1.4)-\sqrt{5.96}}{2*1}=\frac{-1.4-\sqrt{5.96}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.4)+\sqrt{5.96}}{2*1}=\frac{-1.4+\sqrt{5.96}}{2}
$