Question

A weather forecast predicts that the temperature in antarctica will decrease 8 degrees fahrenheit each hour for the next 6 hours. write and solve an inequality to determine how many hours it will take for the temperature to drop at least 36 degrees fahrenheit

Answer 1

Given:
m = -8 degrees/hour, the rate of change of temperature

Let x =  hours 
Let y = temperature, °F
Then y = -8x + b
where b = constant

When x = 0, then y = b.
Therefore b = initial temperature

If the temperature drops by at least 36 °F in the next x hours, then
b - y(6) ≥ 36
b - (-8x + b) ≥ 36
8x ≥ 36
x ≥ 4.5 hours

Answer:  At least 4.5 hours