Line 1: 3x+4y≤12 simplified is y≤3-(3/4)x . The symbol (≤) remains facing the same direction since I did not divide by a negative number. Also, the function means that the value y is less than or equal to 3 minus the function (3/4) multiplied by the independent variable x.

Line 2: x + 3y ≤ 6 simplified is y≤2-(2/3)x . The symbol (≤) remains facing the same direction because I did not divide by a negative number to simplify the function. The function means that the value y is less than or equal to 2 minues the function (2/3) multiplied by the independent variable x.

The last two functions read, x is greater than or equal to 0 and y is greater than or equal to zero.

The solution of the inequalities lies in the combined domains of the functions. Below is the graph for all functions.