Question

Given f(x) = –5x – 1, how do you find f(a – 4)?

Answer 1

f(a - 4 ) = 19 - 5a

Explanation:

f(x) = - 5x - 1 means 'the function expressed in terms of x'

For f(a - 4 ) require to express function in terms of a .

This is done by substituting (a - 4 ) for x .

hence f(a - 4 ) = - 5(a - 4 ) - 1 = - 5a + 20 - 1 = 19 - 5a