Fiona is serving iced tea and lemonade at a picnic. she has only 44 cups in which to serve the drinks. if x represents the number of glasses of iced tea and y represents the number of glasses of lemonade, which equation represents the number of drinks she can serve?

The number of glasses is restricted to 44 cups. So the number of iced tea cups and the number of lemonade cups that she can serve is, maximum, 44. Then, if you call x the number of glasses of iced tea and call y the number of glasses of lemonade, you have that the total number of glasses (cups) is x + y. And the equation that represents the number of glasses that she cacn serve is x + y = 44. You can place it in other equivalent ways, for example, solve for y: y = 44 - x. Those two equations are valid answers because they represent the same equation.