Answer: 7 days
Step-by-step explanation:
Set the two memberships as functions with x representing the days.
(p will stand for the price)
Tom's Gym: p = 12 + 3x
Mike's Gym: p = 5 + 4x
We then want to set them equal to each other:
12 + 3x = 5 + 4x
Balance the equation so x is isolated:
(12 + 3x) - 5 = (5 + 4x) - 5
(7 + 3x) - 3x = 4x - 3x
7 = x
The equations will be equal when x = 7. When 7 days have passed.
Hope this helped. Let me know if you need anything else explained.