Write a system of equations to describe the situation below, solve using any method, and fill in the blanks. Sally, an artist, plans to paint and sell some miniature paintings. She just bought some brushes for $12, and paint and canvas for each painting costs $77; she will sell each painting for $78. Once Sally sells a certain number of her paintings, she will be breaking even. How much will Sally have earned? How many paintings will that be?

Sally's expenses and receipts will both total $ when she has sold of her paintings.