Tolong dijawab beserta caranya

Mapel : Matematika
Materi : Relasi dan Fungsi
Kelas : 8

f(x) = ax - 6

f(2) = 2a - 6 = 1

2a - 6 = 1
2a = 1 + 6
2a = 7
a = 7/2

f(x) = 7/2x - 6

Maka, Nilai f(5)
= 7/2(5) - 6
= 35/2 - 12/2
= 23/2
= 11 ½ → Opsi A