Derivative problem?

Question

Suppose that f(x) is a function with f(100) = 35 and f '(100) = 3. Estimate f(102).

Answer 1

f(102) = f(100) + f'(100)*2 = 35 + 3*2 = 41

Answer 2

f(102)-f(100) = (102-100)*f'(100)
f(102) = 2*3 +35 = 41