X^2-10x-61=0

Solution for X^2-10x-61=0 equation:

X^2-10X-61=0

a = 1; b = -10; c = -61;
Δ = b2-4ac
Δ = -102-4·1·(-61)
Δ = 344
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:

$\sqrt{\Delta}=\sqrt{344}=\sqrt{4*86}=\sqrt{4}*\sqrt{86}=2\sqrt{86}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-10)-2\sqrt{86}}{2*1}=\frac{10-2\sqrt{86}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+2\sqrt{86}}{2*1}=\frac{10+2\sqrt{86}}{2}
$