X^2-22x-87=0

Solution for X^2-22x-87=0 equation:

X^2-22X-87=0

a = 1; b = -22; c = -87;
Δ = b2-4ac
Δ = -222-4·1·(-87)
Δ = 832
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:

$\sqrt{\Delta}=\sqrt{832}=\sqrt{64*13}=\sqrt{64}*\sqrt{13}=8\sqrt{13}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-22)-8\sqrt{13}}{2*1}=\frac{22-8\sqrt{13}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-22)+8\sqrt{13}}{2*1}=\frac{22+8\sqrt{13}}{2}
$