Casio fx-29 - how to enter "y"

[tcab]

Today I noticed my partner pull out an old Casio fx-29 calculator that I didn't know she had!

Here is a photo I found on a website of this calculator.


Needless to say I immediately had a play.

I liked the keyboard feel and the glowing blue display. The time it took to calculate SIN was longer than I thought - about a second. I'm sure HP was never that slow!?

Then I hit the main stumbling block - how to do x^y. I can't find a manual online and not sure how to enter a second number before pressing the x^y key. Can anyone please give me a hint on how to drive this thing?

P.S. Relatedly, found this interesting article about operator precedence in Casio's calculator design history.