The "20" under n means "When n is 20,". Therefor, on the other side of the table, 5n-2 would be 5(20)-2. 5*20=100, 100-2 is 98. The top missing value is 98.
For the other side, it's saying that 5n-2 is 38. You have to work backwards to get your answer. The opposite of -2 is 2, so 38 + 2 is 40. The opposite of *5 is /5, so 40/5 is 8. The bottom missing value is 8.
