1.38x^2-x-5=0

Solution for 1.38x^2-x-5=0 equation:

1.38x^2-x-5=0

We add all the numbers together, and all the variables

1.38x^2-1x-5=0

a = 1.38; b = -1; c = -5;
Δ = b2-4ac
Δ = -12-4·1.38·(-5)
Δ = 28.6
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)-\sqrt{28.6}}{2*1.38}=\frac{1-\sqrt{28.6}}{2.76}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{28.6}}{2*1.38}=\frac{1+\sqrt{28.6}}{2.76}
$