Carly is analyzing a relationship between the profit she makes and the number of candles she sells at her local shop. When she sells 2 candles, her profit is $3.00. When she sells 4 candles, her profit is $6.00. She records this data as the points (2.3) and (4.6). What is the equation that represts the relationship between her profit and the number of candles she sells?​