diketahui f(x)=ax+b,jika f(2)=18 dan f(5)=33 tentukan rumus fungsi f(x) tolong dibantu gan...

f(x) = ax + b

f(2) = 18
a(2) + b = 18
2a + b = 18 ... pers.1

f(5) = 33
a(5) + b = 33
5a + b = 33 ...pers.2

Eliminasi b pada pers.1 dan pers.2:
2a + b = 18
5a + b = 33
__________-
-3a = -15
a = -15 ÷ (-3)
a = 5

Substitusi "a = 5" ke pers.1:
2a + b = 18
2(5) + b = 18
10 + b = 18
b = 18 - 10
b = 8

f(x) = ax + b
f(x) = 5x + 8