When Solve cannot find solutions in terms of radicals to polynomial equations, it returns a symbolic form of the result in terms of Root objects.
You can get numerical solutions by applying N.
You can use NSolve to get numerical solutions to polynomial equations directly, without first trying to find exact results.
|NSolve[poly0,x]||get approximate numerical solutions to a polynomial equation|
|NSolve[poly0,x,n]||get solutions using n-digit precision arithmetic|
|get solutions to a polynomial system|
NSolve can find solutions to sets of simultaneous polynomial equations.