The Rhind Papyrus is the best example of Egyptian mathematics and dates to around 1650 BCE, but its contents date even further back. In its own introduction, the scribe, A’h-mose writes that he is copying material from 1849-1800 BCE. So four thousand years ago, the Egyptians were coming up with all sorts of fascinating materials. An excellent description of this papyrus is available in Eli Maor’s book, Trigonometric Delights, which is actually available online!
Egyptians wrote from right to left and used symbols to indicate numbers as shown below.