ΔABC এ AB = AC, ∠A = 40° হলে, ∠C = কত?

প্রশ্ন: ΔABC এ AB = AC, ∠A = 40° হলে, ∠C = কত?


সমাধান:
ΔABC এ AB = AC
∠C = ∠B

আবার,
∠A + ∠B + ∠C = 180°
40 + ∠C + ∠C= 180°
2∠C = 180° - 40°
2∠C = 140°
∠C = 140°/2
∠C = 70°