tolong kerjakan no 18-22pake jalan cara

18. → Byk anggota B pangkat byk anggota A
= 2³ = 8 cara (C)
19. → Byk anggota A × byk anggota B
= 3 × 3 = 9 cara (B)
20. f = x+2
2 + 2 → 4
4 + 2 → 6
6 + 2 → 8
8 + 2 → 10
Maka, hasilnya C. {4, 6, 8, 10}
21. f(x) → 2x + 3 = -3
2x = -3 - 3
2x = -6
x = -6 / 2
x = -3
22. f(x) = ax - 10
f(-2) → -2a - 10 = 6
-2a = 6 + 10
-2a = 16
a = 16 / -2
a = -8

No 22
= f (-2) = 6
f(x) = ax-10
a. -2-10= 6
-2a= 6+ 10
a = -8