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put this solution on YOUR website!If you graph the three inequalities, you get a shaded right triangle whose vertices are at (0, 0), (2, 0), and (0, 4)
The maximum of 7x + 3y is found when x = 2...there y = 0 and the value is 14.
If you solve 2x + y <= 4 for y and plug it in, you get x + 12 as a max, again found by letting x = 2, and the value is 14...