WILL MARK BRAINLIEST

What is the rate of change of the linear function that has a graph that passes through the points (1, 15) and (–2, 3)?

Only 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, . , -, and / are allowed in your answer. Answers that are mixed numbers must be entered as an improper fraction or decimal.