Diketahui f kurung buka kurung tutup = AX + B jika f(3) = -5 dan f( -2)=10.tentukan Rumus fungsi dan nilai f(5) !

f(x) = ax + b

f(3) = 3a + b = - 5
f(-2) = - 2a + b = 10
---------------------------(-)
5a = - 15
a = - 3

3a + b = - 5
3(-3) + b = - 5
- 9 + b = - 5
b = - 5 + 9
b = 4

f(x) = - 3x + 4
f(5) = - 3(5) + 4 = - 15 + 4 = - 11