x^2+15x-3600=0

Solution for x^2+15x-3600=0 equation:

x^2+15x-3600=0

a = 1; b = 15; c = -3600;
Δ = b2-4ac
Δ = 152-4·1·(-3600)
Δ = 14625
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:

$\sqrt{\Delta}=\sqrt{14625}=\sqrt{225*65}=\sqrt{225}*\sqrt{65}=15\sqrt{65}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-15\sqrt{65}}{2*1}=\frac{-15-15\sqrt{65}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+15\sqrt{65}}{2*1}=\frac{-15+15\sqrt{65}}{2}
$