Nomer 15 tlong jwab kak

Bab Persamaan Kuadrat
Matematika SMP Kelas VIII

15] x² – 4x – 21
= x² + 3x – 7x – 21
= x (x + 3) – 7 (x + 3)
= (x + 3) (x – 7)

◎◎ C ◎◎