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12. the amount of money in a bank account decreased by 21.5% over the last year. if the amount of money at the beginning of the year is represented by ‘n', write 3 equivalent expressions to represent the amount of money in the bank account after the decrease?

What is the anwers for 9+2x=5x-3-x

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.