X^2+140x-1200=0

Solution for X^2+140x-1200=0 equation:

X^2+140X-1200=0

a = 1; b = 140; c = -1200;
Δ = b2-4ac
Δ = 1402-4·1·(-1200)
Δ = 24400
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:

$\sqrt{\Delta}=\sqrt{24400}=\sqrt{400*61}=\sqrt{400}*\sqrt{61}=20\sqrt{61}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(140)-20\sqrt{61}}{2*1}=\frac{-140-20\sqrt{61}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(140)+20\sqrt{61}}{2*1}=\frac{-140+20\sqrt{61}}{2}
$