Answer:
9 hours
Steps:
3x + 20 = 47
3x = 27
x = 9
Step-by-step explanation:
The starting temperature is 20°F, and it rises 3° every hour.
We know in x hours, the temperature will be 47°F.
So our equation is 3x + 20 = 47
Since the temperature is already 20°, we will subtract 20 from 47, leaving us with 27.
What number, multiplied by 3, is 27?
9.
Therefore, we know in 9 hours, the temperature will be 47°F.
Hope this helped :)