Sean has a bag containing x green marbles and two bags containing y blue marbles. He adds 15 marbles to the bag of green marbles
and adds 6 marbles to each bag of blue marbles. The total number of marbles in all three bags is given by the expression (x + 15) + 2(y + 6). Identify an equivalent expression.
She should start on the x axis (the one that's horizontal or goes left to right) and should go to the right first. Right is positive and the first number is a positive three so she would go to the right three units first.
