140x^2-60x-1600=0

Solution for 140x^2-60x-1600=0 equation:

140x^2-60x-1600=0

a = 140; b = -60; c = -1600;
Δ = b2-4ac
Δ = -602-4·140·(-1600)
Δ = 899600
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:

$\sqrt{\Delta}=\sqrt{899600}=\sqrt{400*2249}=\sqrt{400}*\sqrt{2249}=20\sqrt{2249}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-60)-20\sqrt{2249}}{2*140}=\frac{60-20\sqrt{2249}}{280}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-60)+20\sqrt{2249}}{2*140}=\frac{60+20\sqrt{2249}}{280}
$