# Revision history [back]

### Eliminating variables from a system of equations?

I'm (very) new to Sage, but am confused about why I can't get it to solve a simple system like this:

var('x, y, z') eqns = [ x^2 + y^2 == z, x == y]

but solve(eqns, z) gives an empty list back instead of my desired z = 2y^2

 2 No.2 Revision calc314 4081 ●19 ●44 ●109

### Eliminating variables from a system of equations?

I'm (very) new to Sage, but am confused about why I can't get it to solve a simple system like this:

var('x, y, z')
eqns = [ x^2 + y^2 == z, x == y]y]


but solve(eqns, z) gives an empty list back instead of my desired z = 2y^2