Fungsi f(x)=ax+b dgn f(4)=13 dgn f(-2)=1 Tentukan rumus fungsi

f(x)=ax+b dgn f(4)=13 dgn f(-2)=1 

f(4) = a(4) + b = 13 ...................(1)
f(-2) = a(-2) + b = 1 ..................(2)

Dari (1) dan (2)
4a + b = 13
-2a + b = 1  -
---------------------
6a = 12
   a = 2

Subtitusi nilai a ke pers 4a + b = 13
4a + b = 13
4(2) + b = 13
8 + b = 13
b = 13-8
b = 5

Jadi Rumus fungsinya
f(x) = 2x + 5