The square of 4 × (X-5) = (X-5) (x + 5) solves the equation

The square of 4 × (X-5) = (X-5) (x + 5) solves the equation

4(x-5)^2=(x-5)(x+5)
4(x-5)^2-(x-5)(x+5)=0
(x-5)(4(x-5)-x-5)=0
x1=5 x2=5