Diketahui fungsi f(x)=ax+b.jika f(2)=11dan f(4) =17, nilai f(7)=...

f(x) = ax+b

f(2) = 11
2a+b = 11

f(4) = 17
4a+b = 17

2a+b = 11
4a+b = 17
_________ -
-2a = -6
a = 3

2a+b = 11
6+b = 11
b = 5

f(7) = 7a+b
f(7) = 21+5
f(7) = 26

f(x) = ax + b

f(2) = a(2) + b
11 = 2a + b

f(4) = a(4) + b
17 = 4a + b

17 = 4a + b
11 = 2a + b
---------------- -
6 = 2a
a = 3

11 = 2a + b
11 = 2(3) + b
11 = 6 + b
b = 5

f(7) = ax + b
f(7) = 3(7) + 5
f(7) = 21 + 5
f(7) = 26

Maka f(7) = 26