Answer: 10 miles.
Explanation:
Let m the number of miles that each dog is walked.
It is given that Beth does not charge a registration fee for her dog-walking service, but she charges $5 per mile that each dog is walked.
Amount charged by Beth = 5m
Tonya’s dog-walking service charges a registration fee of $20, plus $3 per mile that each dog is walked.
Amount charged by Tonya = 20+3m
We need to find the number of miles m for which Tonya and Beth would charge the same amount.



Divide both sides by 2.

Therefore, for 10 miles Tonya and Beth would charge the same amount.