f(×) = ax + b, f(-1) = 1 dan f(4) = 11 nilai f(8) adalah...

f(x) = ax + b
f(-1) = - a + b = 1
f(4) = 4a + b = 11
-------------------------(-)
- 5a = - 10
a = 2
-a + b = 1
- 2 + b = 1
b = 1 + 2
b = 3
f(x) = 2x + 3
f(8) = 2(8) + 3 = 16 + 3 = 19

Mapel : Matematika
Bab : Fungsi

f(x) = ax + b
f(-1) = -a + b = 1
f(4) = 4a + b = 11
----------------------- -
             -5a  = -10
                  a = -10/-5
                  a = 2

-a + b = 1
-2 + b = 1
       b = 1 + 2
       b = 3

f(x) = ax + b
f(8) = 2.8 + 3
       = 16 + 3
       = 19