【简答题】已知:如图BE∥CF,BE、CF分别平分∠ABC和∠BCD,求证:AB∥CD 证明:∵BE、CF分别平分∠ABC和∠BCD(已知) ∴∠1= ∠ _________ ∠2= ∠ _________ ( _________ ) ∵BE∥CF( _________ ) ∴∠1=∠2( _________ ) ∴ ∠ABC= ∠BCD 即∠ABC=∠BCD ∴AB∥CD( _________ )。
【判断题】AIBN+CF 2 =CF 2 能进行自由基聚合。( )
【简答题】已知:如图,BE,CF为△ABC的高,且BE=CF,BE,CF交于点H,若BC=10,FC=8,则EC=______.
【简答题】What are the thoughts you may get after learing "Discovering Problems: Slim is Beautiful?"
【单选题】May 1610, 120 years after , is still a perilous journey.
【单选题】May is after(在...之后)________.
【简答题】已知AC=BD,AE=CF,BE=DF,问AE∥CF吗?
【简答题】8 They may remain hungry after dinner since the food is even not offered a second time after their polite initially decline
【简答题】已知:如图BE//CF,BE、CF分别平分∠ABC和∠BCD,求证:AB//CD 。 证明:∵BE、CF分别平分∠ABC和∠BCD(已知) ∴∠1= ∠( ),( ) ∵BE//CF(已知) ∴∠1=∠2( ) ∴∠ABC=∠BCD ∴AB//CD( )