X*x-25x-136=0

Solution for X*x-25x-136=0 equation:

X*X-25X-136=0

We add all the numbers together, and all the variables

-25X+X*X-136=0

Wy multiply elements

X^2-25X-136=0

a = 1; b = -25; c = -136;
Δ = b2-4ac
Δ = -252-4·1·(-136)
Δ = 1169
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-25)-\sqrt{1169}}{2*1}=\frac{25-\sqrt{1169}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-25)+\sqrt{1169}}{2*1}=\frac{25+\sqrt{1169}}{2}
$