From the equation, y=58-x, where y is temperature and x is time in hours.
Time from 6 p.m to 9 a.m = 15 hours
Therefore, the value of y= 58 - 15 = 43 fahrenheits
The average rate of change in temperature = temperature divided by time
= 43 / 15 =2.86 Fahrenheit/hour
Therefore, the rate of change in temperature will be given by 2.86 Fahrenheit /hour.
