The temperature in Toronto at noon during a winter day measured 4°C. The temperature started dropping 2° every hour. Which inequality can be used to find the number of hours, x, after which the temperature will measure below -3°C?

Answer 1

-2x + 4 < -3 , where x is the number of hours after noon
or
2x > 7
x > 3.5

notice the switch in the inequality sign because we divided by a negative

Answer 2

The temperature in Toronto at noon during a winter day measured 4°C. The temperature started dropping 2° every hour. Which inequality can be used to find the number of hours, x, after which the temperature will measure below -3°C?