Given the function f(z) = 8z + 5, evaluate and simplify the expressions below. See special instructions on how to enter your answers:
f(a)
f(a + h) =
(f(a + h) - f(a)) / h
Instructions: Simplify answers as much as possible. Expressions such as 4(a + 2) and (a + 5)^2 should be expanded. Also, collect like terms, so 31 + a should be written as 4a.