During a period of extreme cold, the average daily temperature dropped decreased by 11/2°Feach 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 x + 11/2 = 9x + 112 = 9

B x − 11/2 =−9x − 112 =−9

C −11/2x = −9−112x = −9

D 11/2x = 9
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