Question

At midnight, the temperature in a city was 5 degrees Celsius. The temperature was dropping at a steady rate of 2 degrees Celsius per hour.
Write an inequality that represents t, the number of hours past midnight, when the temperature was colder than -4 degrees Celsius. Explain or show your reasoning.

Answer 1

Answer:

t > 4.5

Step-by-step explanation:

T = 5 - 2t

is the equation for the temperature after midnight.

-4 = 5 - 2t  is the point of interest

-9 = -2t

t = 4.5 hrs  so 4:30 is the time the temperature reaches -4

t > 4.5 hrs covers all the time that the temperature is less than -4