Because Macbeth is planning to kill Banquo and Fleance. Banquo states that none of Macbeth's family would be next in line for King but his family will. Macbeth sees the three witches to check that what Banquo was saying is correct.
Act I Scene iii - Good Sir, why do you start and seem to fear things that do sound so fair?
"Ride you this afternoon?"
"Is't far you ride?"
"Goes Fleance with you?"
Well the witches tell him that Banquo's issue will be kings. Not Macbeth's, but Banquo's.
To kill the king, Banquo likes the idea.
"Goes Fleance with you?"
Macbeth sees the ghost of the recently murdered Banquo.
No, Lady Macbeth is not aware that Macbeth has planned the death of Banquo and Fleance.
Macbeth kills him because Banquo starts to work out that Macbeth killed dDuncan
You need to specify. There are a number of scenes between Banquo and Macbeth.
Macbeth killed banquo. Because Macbeth heard the witches say he will also be king. so Macbeth saw him as a threat to the throne and lets just say did something bad to banquo (killed him)
Macbeth kills Banquo in the play and then Banquo's ghost haunts Macbeth.
Macbeth's best friend was Banquo. They fought together in battle before Macbeth's rise to power.
Macbeth kills Banquo in the play and then Banquo's ghost haunts Macbeth.
Macbeth sees the ghost of the recently murdered Banquo.
No, Lady Macbeth is not aware that Macbeth has planned the death of Banquo and Fleance.
Macbeth's soldiers do not kill Banquo, Macbeth hires three murderers to do the job.
Macbeth kills him because Banquo starts to work out that Macbeth killed dDuncan
In Act 3 of Macbeth, Macbeth becomes suspicious that Banquo poses a threat to his throne. He worries that Banquo's descendants will inherit the crown, as the witches prophesied. This suspicion leads Macbeth to plot Banquo's murder.
Macbeth doesn't confide in Banquo because he sees Banquo as a threat to his ambition. Banquo's descendants are said to be kings according to the witches' prophecy, which poses a risk to Macbeth's position as king. Macbeth becomes increasingly paranoid and seeks to eliminate anyone who might challenge his rule.
It is not known who kills Banquo but it is Macbeth who orders for him to be murdered.
In both cases, the ghost that appears in Macbeth is summoned by the guilt and inner turmoil of Macbeth himself. The ghost of Banquo is a manifestation of Macbeth's guilt over his role in Banquo's murder, while the ghost of Lady Macbeth represents his guilt over her death and his descent into madness.
You need to specify. There are a number of scenes between Banquo and Macbeth.