X^2-11x+13-25=0

Solution for X^2-11x+13-25=0 equation:

X^2-11X+13-25=0

We add all the numbers together, and all the variables

X^2-11X-12=0

a = 1; b = -11; c = -12;
Δ = b2-4ac
Δ = -112-4·1·(-12)
Δ = 169
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{169}=13$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-11)-13}{2*1}=\frac{-2}{2}
=-1
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11)+13}{2*1}=\frac{24}{2}
=12
$