Let t represent time in hour
Temperature in Raleighis can be given as 75 + 2t
Temperature in Charlotte can be given as 82 + t
For them to be in the same temerature:
75 + 2t = 82 + t
Collect like term and then solve for t
2t - t = 82 - 75
t = 7 hours
Hence, they will have the same temperature at the 7th hours