The Egyptians built pyramids as the tombs of their kings.
The Egyptians built the pyramids as buril places for the pharoahs.
The ancient Egyptians built the pyramids for pharaohs in the afterlife.
No. The pyramids were built by real people - the Egyptians.
because they believed in afterlife so they built the pyramids to put the dead kings in to keep them safe. In terms of grammar, both are acceptable. However, I would recommend using "Egyptians built pyramids" because implicit in the usage of the present perfect (the "have done something" tense) is that the action has continued to the present, which is not the case as concerns Egyptians building pyramids.
Built pyramids.
pyramids
The Egyptians.
No, they built pyramids
No they were built by the Egyptians
Pyramids are built for praying to the Egyptian Gods. They were also built because egyptians believed that when you die you bring all of your riches with you. (also how much money you have gets you into "heaven") They built the pyramids to contain their bodies and riches, so that in the afterlife the "rich" folk will have their belongings with them.
Over ramids were built by the Egyptians.