X2+60x-100=40

Solution for X2+60x-100=40 equation:

X2+60X-100=40

We move all terms to the left:

X2+60X-100-(40)=0

We add all the numbers together, and all the variables

X^2+60X-140=0

a = 1; b = 60; c = -140;
Δ = b2-4ac
Δ = 602-4·1·(-140)
Δ = 4160
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:

$\sqrt{\Delta}=\sqrt{4160}=\sqrt{64*65}=\sqrt{64}*\sqrt{65}=8\sqrt{65}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(60)-8\sqrt{65}}{2*1}=\frac{-60-8\sqrt{65}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(60)+8\sqrt{65}}{2*1}=\frac{-60+8\sqrt{65}}{2}
$