What do s the solution to this system of equations? 2/3x+y=6 -2/3x-y=2

Itook a better photo of the question so y’all can see it i hope it’s a fine photo

Bill works as a waiter and is keeping track of the tips he ears daily. about how much does bill have to earn in tips on sunday if he wants to average $22 a day? tips by day tips (dollars) monday tuesday wednesday thursday friday saturday $14 $22 $28 $36

Answer! if you don’t mind, can you explain