4x^2+140x-2000=0

Solution for 4x^2+140x-2000=0 equation:

4x^2+140x-2000=0

a = 4; b = 140; c = -2000;
Δ = b2-4ac
Δ = 1402-4·4·(-2000)
Δ = 51600
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:

$\sqrt{\Delta}=\sqrt{51600}=\sqrt{400*129}=\sqrt{400}*\sqrt{129}=20\sqrt{129}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(140)-20\sqrt{129}}{2*4}=\frac{-140-20\sqrt{129}}{8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(140)+20\sqrt{129}}{2*4}=\frac{-140+20\sqrt{129}}{8}
$