Banquo probably doen't know for sure about how Macbeth is planning on killing Duncan so he can become king. Even if Banquo did know, he is a very loyal friend to Macbeth and will keep all of his suspicions to himself.
Which is ironic, because Mabeth ends up hiring murderers to kill Banquo, which goes to show you that Macbeth really isn't that loyal.
And then Macbeth asked Macbeth if he confronted Macbeth on killing Macbeth with Macbeth.
Macbeth's coronation
Macbeth and his wife plan to blame the guards for killing the King. Indeed, after the murder, Macbeth slays them both claiming that they had commited the deed. Almost immediately, however, the sons of Duncan (Malcolm and Donalbain) decide to flee since they fear that they will be suspected of either killing their father or hiring the killer. Later, it is discussed that they are suspects, but it is also made clear that most people recognize that it's really Macbeth who has done it.
Macbeth believes he has to kill Duncan's guards in case they heard anything happen in the room while Macbeth was killing Duncan.
she talked him into killing the King by accusing Macbeth of being weak and cowardly
Lady Macbeth talked Macbeth into killing his cousin, King Duncan of Scotland, who was a guest in his house at the time.
And then Macbeth asked Macbeth if he confronted Macbeth on killing Macbeth with Macbeth.
She helps Macbeth out by tricking him into killing the king. :P
Macbeth's coronation
Macbeth and his wife plan to blame the guards for killing the King. Indeed, after the murder, Macbeth slays them both claiming that they had commited the deed. Almost immediately, however, the sons of Duncan (Malcolm and Donalbain) decide to flee since they fear that they will be suspected of either killing their father or hiring the killer. Later, it is discussed that they are suspects, but it is also made clear that most people recognize that it's really Macbeth who has done it.
Macbeth kills Banquo in the play and then Banquo's ghost haunts Macbeth.
Macbeth believes he has to kill Duncan's guards in case they heard anything happen in the room while Macbeth was killing Duncan.
she talked him into killing the King by accusing Macbeth of being weak and cowardly
Because you don't mess with Lady MacBeth
"Sleep no more, Macbeth doth murder sleep."
The reaction between Lady Macbeth and Macbeth is initially very different after they kill Duncan. Lady Macbeth is enthusiastic but Macbeth regrets his actions.
After killing Duncan, Macbeth could not sleep. He feels the guilt and is terrified