x²/(x-5)+25/(5-x)
=x²/(x-5) - 25/(x-5)
=(x²-25)/(x-5)
=(x+5)(x-5)/(x-5)
=x+5
1/x-1/(x-1)
=[(x-1)-x]/[x(x-1)]
=-1/[x(x-1)]