# solve equation with two variables over RR

Hi,

I have a problem with the following code (minimal example) in SageMath 8.7 notebook:

```
x, y = var('x,y', domain=RR)
solve(x == 0, x, y)
```

when executed, I get the following error:

```
/opt/sagemath-8.7/local/lib/python2.7/site-packages/sage/symbolic/relation.pyc in _solve_expression(f, x, explicit_solutions, multiplicities, to_poly_solve, solution_dict, algorithm, domain)
1357 if to_check:
1358 for ix, soln in reversed(list(enumerate(X))):
-> 1359 if soln.lhs().is_symbol():
1360 if any(a.contradicts(soln) for a in to_check):
1361 del X[ix]
AttributeError: 'list' object has no attribute 'lhs'
```

both

```
x, y = var('x,y')
solve(x == 0, x, y)
```

and

```
x, y = var('x,y', domain=RR)
solve(x == 0, x)
```

work as expected.

I am sorry if that question a already been posted, I don't know which keyword to use.

A bug, IMHO...