Fungsi f(x) = ax + b. Jika f(2) = -2 dan f(-3) = 13, nilai f(4) adalah ....

-2 = 2a + b
13 = -3a + b
eliminasikan.
15 = 5a
a = 3

-2 = 2.3 + b
-2 = 6 + b
-2 - 6 = b
-8 = b

f(4) = 4a + b
f(4) = 4.3 + (-8)
f(4) = 12 + (-8)
f(4) = 4

Jadi , f(4) = -8 ,,,,,,,,,,,,,,,,,