✨ 最佳解答 ✨
△OAB、△OBC、△OAC 皆為等腰三角形,因為兩腰都是半徑。
=> ∠OCB = 40
假設:
△OAC 的底下兩個角的度數同為 a
△OAB 的底下兩個角的度數同為 b
=>
a +40 = b +40 +14
a -b = 14
a +a +40 +40 +b +b = 180
2a +2b = 100
a +b = 50
=>
a = 32
b = 18
(A)
a +b = 32 + 18 = 50
(B)
40 +a = 40 + 32 = 72
(C)
180 -2b = 180 - 36 = 144
(D)
a = 32