Answer:
f(x) = - 4x + 4
Step-by-step explanation:
A linear function has the form
f(x) = ax + b, thus
f(0) = a(0) + b = 4, that is
0 + b = 4 , hence b = 4
f(3) = 3a + b = - 8 ← substitute b = 4
3a + 4 = - 8 ( subtract 4 from both sides )
3a = - 12 ( divide both sides by 3 )
a = - 4, thus
f(x) = - 4x + 4
