40x*x+94x-39=0

Solution for 40x*x+94x-39=0 equation:

40x*x+94x-39=0

We add all the numbers together, and all the variables

94x+40x*x-39=0

Wy multiply elements

40x^2+94x-39=0

a = 40; b = 94; c = -39;
Δ = b2-4ac
Δ = 942-4·40·(-39)
Δ = 15076
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{15076}=\sqrt{4*3769}=\sqrt{4}*\sqrt{3769}=2\sqrt{3769}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(94)-2\sqrt{3769}}{2*40}=\frac{-94-2\sqrt{3769}}{80}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(94)+2\sqrt{3769}}{2*40}=\frac{-94+2\sqrt{3769}}{80}
$