During a period of extreme cold, the average daily temperature dropped decreased by 112°F each day. How many days did it take for the temperature to decrease by 9°F? Which equation would you use to find the solution?
A d + 112 = 9d + 112 = 9
B d − 112 =−9d − 112 =−9
C −112d = −9−112d = −9
D 112d = 9