diketahui fungsi f+(×)=a×+b jika f(2)=-2 dan f+(3)=13 tentukan nilai f(4)

f(x) = ax + b
f(2) = -2 ==> 2a + b = -2....(1)
f(3) = 13 ==> 3a + b = 13....(2)
---------------------- -
-a = -15.==> a = 15
dari (1), 2a + b = -2
2.15 + b = -2
b = -2 - 30
b = -32
maka f(x) = 15x - 32
f(4) = 15.4 -32
= 60 - 32
= 28