Multiple choice Sum of xy, x + y and y + xy is 2xy + 2x + y 3xy + 2y 2xy + x + y 2xy + x + 2y Reveal answer Fill a bubble to check yourself D Correct answer Explanation Sum the terms: (xy) + (x + y) + (y + xy). Grouping like terms gives (xy + xy) + x + (y + y), which results in 2xy + x + 2y.