We are getting x=1/2,3.both are positive

|X|= X, when X>0

=- X when X<0

Similarly ,|-X| =-X when X <0

=-(-X) when X>0

2|X|-|X|=2X-(-(-X))=2X-X=X

|X|= X, when X>0

=- X when X<0

Similarly ,|-X| =-X when X <0

=-(-X) when X>0

2|X|-|X|=2X-(-(-X))=2X-X=X