Jason works as an administrative assistant for a local lawyer's office. The office is running low on pens and notepads, so he is asked to buy $150 worth of pens and notepads. Pens cost $1, and notepads cost $2. If the number of pens he buys is represented by x and the number of notepads he buys is represented by y, the situation can be given by x + 2y = 150, where 0 sxs 150, 0 sys 75 and x and y can take only integer values.