x^2+200x-15=0

Solution for x^2+200x-15=0 equation:

x^2+200x-15=0

a = 1; b = 200; c = -15;
Δ = b2-4ac
Δ = 2002-4·1·(-15)
Δ = 40060
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:

$\sqrt{\Delta}=\sqrt{40060}=\sqrt{4*10015}=\sqrt{4}*\sqrt{10015}=2\sqrt{10015}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(200)-2\sqrt{10015}}{2*1}=\frac{-200-2\sqrt{10015}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(200)+2\sqrt{10015}}{2*1}=\frac{-200+2\sqrt{10015}}{2}
$