There are multiple equations that would fit this description, but one of them could be something like this:

Hope that helped =)
Answer:
220 + 242+ 363= 825 seats are in the amphitheater.
Step-by-step explanation:
Answer:
3,6 I think is the range.
Answer: -12
Step-by-step explanation:
if you'd like to convert a Fahrenheit temperature to an approximate Celsius temperature: Start with the temperature in Fahrenheit
Yes, the extraneous solution is x=7