Tolong bantu jawab pakai cara yaa

Bab Trigonometri
Matematika SMA Kelas X

tan A = BE/AB
tan 30° = 4√3 / AB
1/√3 = 4√3 / AB
AB = 4√3 x √√3
AB = 4 x 3
AB = 12 cm

AC = 12 + 6
      = 18 cm

tan A = DC/AC
tan 30° = DC / 18
1/√3 = DC / 18
DC = 18 / √3
DC = (18√3) / (√3 / √3 )
DC = (18/3) √3
DC = 6 √3 cm