A small bakery has two rules for a day. The oven holds at most 4 trays in all, so x + y ≤ 4…

A small bakery has two rules for a day. The oven holds at most $4$ trays in all, so $x + y \le 4$. The orders need at least $10$ units of effort, where a tray of loaves counts $1$ unit and a tray of cakes counts $2$ units, so $x + 2y \ge 10$. Also $x \ge 0$ and $y \ge 0$. First find the largest value of $x + 2y$ over the points with $x + y \le 4$. Then decide how many feasible points the bakery has.