if anna is x years old and her sister is 5 five years older the eqasion would be x=5-5x but there is no further information for the answer. You need to know how old anna is to answer the question. Did you write it correctly
Because We know that Anna is X, and we also know that she is 5 years younger we know that her sister's age must be x, as it is asking for her age 5 years ago.
