jika besar sudut BAC = 40 derajat. tentukan sudut DBC

Kelas 8 Matematika
Bab Lingkaran

∠BDC  = ∠BAC
∠BDC = 40°

Karena AC = BD = diameter = 180°

∠BCD = 1/2 . 180°
∠BCD = 90°

∠DBC = 180° - 90° - 40°
∠DBC = 50°