How do the 3 witches make Hecate angry?

Answer: Hecate is angry because the 3 witches have made prophecies to Macbeth without telling her.

She feels they gave an unworthy man a prophecy, and they did not consult her.

Explanation:

In Shakespeare's "Macbeth," Hecate is the goddess of witchcraft, who is angry at the three witches for predicting the future for Macbeth. She believes that he chiefest enemy of mankind is security or overconfidence. In that respect, the witches lead Macbeth off the right direction by deceiving him into thinking he is greater than fate and making him overly sure of himself.