X= {(2, 3), (2, 4), (2, 5), (2, 6)} is x a function and why? no, each ordered pair in this list has the same first element. yes, no two ordered pairs in this list has the same second element. yes, there is more than one ordered pair in this list. no, there is a limited number of ordered pairs in this list.

The students at jefferson middle school are raising money for a charity by selling t-shirts and hats. the number of t-shirts sold was 3 times the number of hats. the profit was $5 for each t-shirt sold and $2.50 for each hat sold. the students raised $840 for the charity. they used the system below to analyze their success and found the solution to be (144, 48). 5x+2.50y=840 x=3y how much did they earn from t-shirt sales?