What is the inverse function of y=x^2-7

Asocial networking site currently has 400,000 active members, and that figure is predicted to increase by 32% each year. the following expression represents the number of active members on the site after t years.

Jada has a monthly budget for her cell phone bill. last month she spent 120% of her budget, and the bill was 60$. what is jada’s monthly budget

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