The inequalities are,
3x+4y ≤ 60, x+3y ≤ 30, x ≥ 0, y ≥ 0.
For the inequality,
3x+4y ≤ 60(1)
Put the value, x=0 in equation (1).
3( 0 )+4y = 60 4y = 60 y = 15
Put the value, y = 0 in equation (1).
3x+4( 0 ) = 60 3x = 60 x= 20
For the inequality,
x+3y ≤ 30(2)
Put the value, x=0 in equation (2).
( 0 )+3y = 60 3y = 60 y = 20
Put the value, y = 0 in equation (2).
x+3( 0 ) = 30 x = 30
For the inequality x ≥0, the value of x can be equal to 0or greater than 0.
For the inequality y ≥0, the value of y can be equal to 0or greater than 0.
For all the four inequalities, the graph is shown as:
In the graph, the inequality x ≥0 is shown by green color, the inequality y ≥0 is shown by black color, the inequality x+3y≤ 30 is shown by red color and the inequality 3x+4y ≤ 60 is shown by blue color.
Thus, the region ABDC as shown in the graph is the graph of the system of all four inequalities.