Answer:
9.3˚F
Step-by-step explanation:
Lets say that the temperature at the beginning of the day was X. The problem says that the temperature doubles, so we would multiply X with 2 to get 2X. Then, the problem says that the temperature decreased by 12.1 degrees, so the equation would become 2X - 12.1 . At the end of the day, the temperature was -6.5˚ so we know that 2X - 12.1 = -6.5˚ . Then, you just solve the equation to get 9.3˚F. Hope this helps!