Answer:
For 12 minutes, the cost of both companies will be equal and the cost will be 72¢.
Explanation:
We are given the following information:
Let x be the number of minutes where the cost of both companies is equal.
Company A charger = 36 cents and 3 cents per minute
Company B charges = 6 cents per minute
Cost of Company A after x minutes:

Cost of company B after x minutes:

Equating the two equations:

Thus, for 12 minutes, the cost of both companies will be equal and the cost will be 72¢.