0.09x^2-4x-5.6=0

Solution for 0.09x^2-4x-5.6=0 equation:

0.09x^2-4x-5.6=0

a = 0.09; b = -4; c = -5.6;
Δ = b2-4ac
Δ = -42-4·0.09·(-5.6)
Δ = 18.016
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{-(-4)-\sqrt{18.016}}{2*0.09}=\frac{4-\sqrt{18.016}}{0.18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+\sqrt{18.016}}{2*0.09}=\frac{4+\sqrt{18.016}}{0.18}
$