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Question 120·Hard·Linear Inequalities in One or Two Variables

Integers xx and yy must satisfy the system of inequalities

{2x+3y18xy>1\begin{cases} 2x + 3y \le 18 \\ x - y > 1 \end{cases}

and also lie in the window 3x8-3 \le x \le 8 and 3y8-3 \le y \le 8.

How many ordered pairs (x,y)(x, y) satisfy all of these conditions?