Final answer:
Menelaus did not avenge Agamemnon due to his weakened army, ships being blown off-course to Egypt, and his reluctance to leave Helen alone in the house.
Step-by-step explanation:
Menelaus did not avenge Agamemnon because his depleted army could not match up to Aegisthus's. Additionally, his ships were blown off-course to Egypt, which further hindered his revenge. Furthermore, Menelaus did not dare leave Helen alone in the house again, as she was the cause of the Trojan War and her presence could have led to more chaos.
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