Cho ΔABC vuông tại A lấy D thuộc tia đối của tia AB sao cho AD=AB.               a) Chứng minh CA là phân giác của góc BCD và góc CBA= góc CDA.               b) Kẻ AH ⊥BC,AK⊥DC.Chứng minh BH=DK.

Thu gọn đa thức sau:

"we enjoyed ourselves  so much last night" they said to her                                        "we weren't here last year" I ssaid to him

The boy can't  swallow the pill because it's too big. -> The pill                                        We can't go to the movie because it's too late.-> It is                                                 The weather is too cold for us to go swimming.->It is

It is such an expensive house that we can't afford to buy it.                                     -> The house______                                                                                            That chair is so uncomfortable that I don't want to sit on it.                                             -> The chair________                                                                                                  You aren't well.You shouldn't go to school today.                                                             ->You aren't________________                                                                                      I can't help you because I am not strong.                                                                     -> I am_________________________                                                                                   He didn't want to wait for you because I wasn't patient.                                                 -> I wasn't__________________                                                                         The music was too loud for me to hear.                                                                          -> The music wasn't________________                                                                                    

1) "They are from England",she said to me.                                                                2) "We can't play as well as we used to",they said to me.                                   3) "We won't help you with this work",they said to her.                                           4) "He devoted his life to education",she said to them.                                          5) "The flight to Canada was cancelled yesterday evening",he said to me.     6) "They are having lunch with Mr.Minh at the restaurant",she said to us.      7) "They had pointed out the fire before the firemen arrived.                             8) "He said "He died of heart disease",they said to her

1) "They are from England",she said to me.                                                                2) "We can't play as well as we used to",they said to me.                                   3) "We won't help you with this work",they said to her.                                           4) "He devoted his life to education",she said to them.                                          5) "The flight to Canada was cancelled yesterday evening",he said to me. 6) "They are having lunch with Mr.Minh at the restaurant",she said to us. 7) "They had pointed out the fire before the firemen arrived.                             8) "He said "He died of heart disease",they said to her

Cho Δ ABC cân tại A,đường cao AM.                                                                      a) Chứng minh ΔAMB=ΔAMC                                                                                   b) Lấy D thuộc AB,E thuộc AC sao cho BD = CE.Chứng minh MD = ME.             c) Chứng minh ΔADM=ΔAEM