Jerry started doing sit-ups everyday. The first day he did 15 sit-ups. Every day he did 2more sit-ups than he had done the previous day. Today Jerry did 33 sit-ups. Write an equation that could be solved to find the number of days Jerry has been doing sit-ups, not counting the first day. Let n represent the number of days. An equation that can help Jerry to find the number of days he has been doing sit-ups is given by...

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