Hello,
solve(2) uses a global range of your own executable, that can be set in Tools > Options > Calculation > Roots (range); to have more control it is better to use solve(4) (the number is how many arguments are rquested by the function);
for roots, the syntax is roots(functions,unknowns) or roots(functions,unknowns,guess) (roots(2) and roots(3))
wiki:
roots ,
solve
If you like my plugins please consider to support the program buying a license; for personal contributions to me: paypal.me/dcprojects