In what year did the English start using the symbol of pie for pie?

Answer 1

First of all to correct your English Grammar.

'Pie' is the foodstuff that you eat. e.g. Apple Pie or Meat pie.

The Mathematical symbol is 'pi' NO letter 'e'!!!!

It is the modern spelling of the small case Classical Greek letter 'p'.

Answer 2

Pi as a symbol was first used by the English mathematician William Jones. In 1706 he wrote that 3.14159=

Euler, in 1737, used this symbol and it became the worlds standard symbol for pi after that.