Graphically maximize `Z = 6x + 9y` subject to the constraints `2x - y ge 0, 2x + y ge 8, x + 11 y le 80, x ge 0, y ge 0`.

Graphically Minimize Z = 6x + 3y subject to the constraints 4x + y ge 80, x .+ 5y ge 115, 3x + 2y le 150, x ge 0, y ge 0

Graphically maximize Z = 3x + 9y , subject to the constraints x + 3y le 60, x + y ge 1 0, x le y, x ge 0, y ge 0

Graphically Minimize Z = 4x + 3y subject to the constraints 3 x + y ge 90, x + 5y ge 100, 8x + 5y le 400, x ge 0, y ge 0 .

Graphically Minimize Z = 7x + 4y subject to the constraints 5x + 2y ge 100, 3x + 5y ge 150, 9x + 5y le 360, x ge 0, y ge 0 .

Maximize Z = 22x + 44y subject to the constraints x + y ge 3, 3x + 8y le 24, x - y ge 0, x, y ge 0 .