Hello! The equation that would be used to solve this problem is 25.59 = 9.99 + 0.05m. To find out how many minutes Shelly used for the month, let’s subtract 9.99 from both sides. When we do, we get 15.6 = 0.05m. Now, divide each side by 0.05 to isolate the “m”. When we do that, we get 312. Shelly used 312 minutes in a month. m = 312.
