Answer:
In Act 2, Scene 3, when Malcolm and Donalbain receive the news that their father is dead, they realize their lives are in danger. Donalbain states,
"What should be spoken here,
where our fate,
Hid in an auger-hole, may rush, and seize us?
Let's away..."
Donalbain is aware that staying near Macbeth is dangerous, so they both agree to flee the country. Malcolm will flee to England and Donalbain to Ireland.
Explanation: