Can someone please help me NO LINKS!!!

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Pepe and leo deposits money into their savings account at the end of the month the table shows the account balances. if there pattern of savings continue and neither earns interest nor withdraw any of the money , how will the balance compare after a very long time ?

If g^-1(x) is the inverse of g (x) which statement must be true