Answer:
X= 7
Step-by-step explanation:
The temperature at 9 am = -14.7°F
Between 9am and 12 pm = -14.7 + 17.8 = 3.1°F
Between 12pm and 3 pm = 3.1+5.1 = 8.2°
Between 3pm and 6 pm = 8.2-14.5 = -6.3°F
-30.78!