y=12 bc they said y represented the amount of minutes so now you have 12= 2x +1 then it says you talked on the phone on the fourth day of the month, and the number of days (x) represents the day of the month and bc its the 4th x=4 so now you've got 12=2(4)+1 which goes to 12=8+1, which would be 9 and 9 does not equal 12
therefore they are wrong.