Hi;

one of the simplest way would be creating the variables ´x´ and ´y´ then attributing them the values you want to. Consider this:

[x^2+y x^2-2y] [ENTER]

2 'x' [STO]

1 'y' [STO]

[->NUM]

Alternatively you can store the initial expression in a separate variable, say 'EQ1', with the following sequence:

[x^2+y x^2-2y] 'EQ1' [STO]

2 'x' [STO]

1 'y' [STO]

'EQ1' [->NUM]

This way, you could attribute x and y other values, say 3 and 4, like this:

3 'x' [STO]

4 'y' [STO]

'EQ1' [->NUM]

There are other ways, for sure. This is one of them, though.

Cheers.

Luiz (Brazil)

*(PS: there may be errors, I have no calculator at hands, now...)*

*Edited: 18 Apr 2007, 8:10 p.m. *