ΌഃʿЧ�ɚ�9.33
ਞڝྡ�̬ᗙҖ ABCD ձ EFGH ϞӚϞ̙ঐ݊
ΌഃྡҖ� 120°
95°
A
B
C
D
70°
EF
G
H
ί ABCD ʕ�
+ABC + 95c = 180c �Νࣙʫԉ�AD # BC�
+ABC = 85c
+BCD + 120c = 180c �Νࣙʫԉ�AD # BC�
+BCD = 60c
a +EFG = 70c
` +EFG ၾ ABCD ԉேʔഃ�
` ABCD ձ EFGH ӚϞ̙ঐ݊ΌഃྡҖ�
ܓ二
例例 15
解
ABCD ձ EFGH ʔՈ௪�࿁Ꮠ
ԉഃ�ٙሯ�
◀
Շࡈ̬ᗙҖٙהϞ࿁Ꮠᗙഃ (SSSS) אהϞ࿁Ꮠԉഃ (AAAA)
ࣛ�̴ࡁ݊щɓ֛Όഃ�ᜫҢࡁீཀሙੀݺਗ 9.1 ɓઞӺ�
ਞڝྡ�̬ᗙҖ ABCD ձ EFGH ϞӚϞ̙ঐ݊ΌഃྡҖ�
65°
80°
A D
C
B
110°
E H
G
F
15
即時訓練即時訓練
➥ ୦ᕚ 9C 14
࣬ኽהഗٙ༟ࣘ�̙щႭ
(a) ձ (b) ٙ࿁ྡҖ
ɓ֛݊ΌഃྡҖճ�
(a)
(b)