The temperature has been going down at a constant rate. In 3 hours it went down 15 degrees. Which expression best shows the temperature change each hour?

The correct expression is -15 ÷ 3.

To find the temperature change each hour, you take the total change in temperature (which is -15 degrees) and divide it by the number of hours (3). This gives you the rate of temperature change per hour:

(-15 ÷ 3 = -5) degrees per hour.

So, the temperature decreases by 5 degrees each hour. If you have more questions or need further assistance, feel free to ask!