The answer is 5 months, with the cost of $85. You can find this answer by first writing the charges as 12x + 25 and 10x + 35. Then, you set them equal to each other and solve to find x, which is the number of months.
12x + 25 = 10x + 35
- 10x
2x + 25 = 35
- 25
2x = 10
÷ 2
x = 5
Now that we know what x is, we can substitute it in and get 10(5) + 35 = 50 + 35 = 85.
I hope this helps!
