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x straight angle: $QDQJOHZLWKPHDVXUHLVDVWUDLJKWDQJOH
x vertical angles7ZRDQJOHVRQRSSRVLWHVLGHVRIWKHSRLQWRILQWHUVHFWLRQRIWZRLQWHUVHFWLQJOLQHVDUH
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Notation
x 3RLQWVDUHODEHOHGZLWKFDSLWDOOHWWHUV
x $OLQHWKURXJKSRLQWVA and B is denoted ABHJJG.
x 7KHOLQHVHJPHQWFRQQHFWLQJSRLQWVA and B is denoted AB.
x 7KHOHQJWKRIWKHOLQHVHJPHQWAB is denoted AB.
x &RQJUXHQWOLQHVHJPHQWVDUHGHQRWHGAB#CD.2QGLDJUDPVFRQJUXHQWOLQHVHJPHQWVDUHJLYHQWKH
VDPHPDUNLQJV
x 7KHDQJOHJLYHQE\WZROLQHVHJPHQWVPQ and QR is denoted PQR or RQP.8QOHVVWROG
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x &RQJUXHQWDQJOHVDUHGHQRWHG#PQR ABC.2QGLDJUDPVFRQJUXHQWDQJOHVDUHJLYHQPDWFKLQJ
ODEHOV
x 3HUSHQGLFXODUOLQHVRUOLQHVHJPHQWVDUHGHQRWHGABACD.
Result
x YHUWLFDODQJOHWKHRUHP 9HUWLFDODQJOHVDUHFRQJUXHQW
Summary
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IRUH[DPSOHHYHQWKRXJKZHIHHOWKDWZHKDYHDJRRGLQWXLWLYHXQGHUVWDQGLQJRIZKDWWKHVHFRQFHSWVPHDQ
:HEHJLQWKLVOHVVRQUHO\LQJRQRXULQWXLWLRQWRHVWDEOLVKWKHQRWDWLRQDQGODQJXDJHWKDWLVQRZVWDQGDUGLQWKH
VWXG\RIJHRPHWU\7KHSKLORVRSKLFDOFRQFHUQVRISLQQLQJGRZQZKDWWKHVHEHJLQQLQJWHUPVPHDQOHDGXVWRWKH
SUREOHPRIFLUFXODUUHDVRQLQJDQGWKHQHHGIRUVHWWLQJXQGH¿QHGWHUPVFRXSOHGZLWKSRVWXODWHV
:LWKSKLORVRSKLFDOGLI¿FXOWLHVLQFKHFNZHHQGWKHOHVVRQZLWKWKHODQJXDJHDQGQRWDWLRQRIDQJOHV