Answer: both services will cost the same if it is for 3 hours service.
Step-by-step explanation: Hope this helps.
Define x: Let x be the number of hours
Derrick Dogs sitting:
Fixed charged=$12
Hourly change=$5
Total charge=12+5x
Darlene dog sitting:
Fixed charged=$18
Hourly change=$3
Total charge= 18+3x
Find the total number of hours so that both cost are the same:
12 + 5x = 18 + 3x
5x - 3x = 18 - 12
2x = 6
x = 3
ANSWER: both services will cost the same if it is for 3 hours service