Jerry started doing sit-ups every day. The first day he did 12 sit-ups. Every day after that he did 4 more sit-ups than he had done the previous day. Today Jerry did 36 sit-ups. Enter an equation that could be solved to find the number of days Jerry has been doing sit-ups, not counting the first day.
The equation
______d + ______ = _______
can help find the number of days Jerry has been doing sit-ups