Answer:
5 degrees
Step-by-step explanation:
First let's find out what the total change in degrees was. This should be 51 degrees to reach 0, plus 9 more to reach -9
51 + 9 = 60
Now we need to find how many hours we are dealing with. Just counting (12 pm to 1 pm is 1 hour, 1 pm to 2 pm is another hour, and so on...) we find that we have 12 hours.
So, now we just divide the degrees by the hours and get
60/12 = 5
You can also double check this by doing
51-5-5-5-5-5-5-5-5-5-5-5-5 = -9
