How do you write this quadratic equation using substitution

Sorry guys but as you have a small brain

James adds two numbers a + b. sally adds the same two numbers but reverse the order b + a what property of addition assures us that james and sally will get the same sum

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