Respuesta :
[tex]12x -3y \leq -21\\\\\implies 12x +21 -3y \leq 0\\\\\implies 12x +21 \leq 3y\\\\\implies 3(4x +7) \leq 3y\\\\\implies 4x+7 \leq y\\\\\implies y \geq 4x+7[/tex]
[tex]12x -3y \leq -21\\\\\implies 12x +21 -3y \leq 0\\\\\implies 12x +21 \leq 3y\\\\\implies 3(4x +7) \leq 3y\\\\\implies 4x+7 \leq y\\\\\implies y \geq 4x+7[/tex]