For f(x) = x-1, find f(x+h)?

Question

I seem to be hitting a wall with difference quotient problems. For this one I have f(x) = x - 1, find f(x+h)

f(x+h) = (x + h) - 1?
I'm not exactly sure if that's how the h should be applied or if f(x+h)= x+ h -1

From f(x+h)=(x+h) - 1 I expanded it into the difference quotient

f(x) = x -1
f(x+h)= (x+h) -1
f(x+h) - f(x) / h
(x+h) -1 - x - 1 / h
(x)-1 -x -1?

Answer 1

if f(x) = x-1
and then i change x by 5
then:
f(5) = x-1
= 5-1=4 or f(5)=4
and then i change x by x+h
then:
f(x+h) = (x+h)-1
= x+h-1

Answer 2

f(x) = x - 1
f(a) = (a) - 1 = a - 1, f(b) = (b) - 1 = b -1, f(a + 2) = (a + 2 ) - 1
simply substitute x with the given value.
In the given problem replace x with (x + h)
f(x + h) = (x + h) - 1 = x + h -1

Answer 3

f(x) = x-1
f(x+h) = x + h -1 = x - 1 + h
f(x+h) = f(x) + h

Answer 4

Both are correct.