f (3) = 11 f (6) = 20 Tentukan Rumus Fungsi

f(x) = ax + b

f(6) = 6a + b = 20
f(3) = 3a + b = 11
-------------------------- ( - )
》 3a = 9
》 a = 9 ÷ 3 = 3

6a + b = 20
6.3 + b = 20
18 + b = 20
b = 20 - 18
b = 2

a = 3
b = 2

Rumus fungsi =
f(x) = 3x + 2

f(3)=3a+b=11
f(6)=6a+b=20
_______ -
-3a =-9
a=-9/-3
a=3
3a+b=11
3(3)+b=11
b=11-9
b=2
rumus fungsi = ax+b
=>3x+2