Question

F(x)=x^2-6x-27 over x^2 -1 is the answer -4 and for T=1/5(x-y+z) is this answer correct x+z-y

Answer 1

I do not know how you got -4

there is nothing I can do with
(x^2-6x-27) / (x^2-1)
but factor it
(x-9)(x+3)/[ (x-1)(x+1) ]
that is zero at x = 9 and at x = -3
that is undefined at x = +1 and at x = -1

T is undefined if
x-y+z = 0