Answer :
9x + 12y = 48
9x - 9x + 12y = 48 - 9x
12y = 48 - 9x
12 12
y = 4 - 3/4x
9x + 12(4 - 3/4x) = 48
9x + 48 - 9x = 48
9x - 9x + 48 = 48
0x + 48 = 48
-48 -48
0x = 0
0 0
x = 0
9(0) + 12y = 48
0 + 12y = 48
12y = 48
12 12
y = 4
(x, y) = (0, 4)
9x - 9x + 12y = 48 - 9x
12y = 48 - 9x
12 12
y = 4 - 3/4x
9x + 12(4 - 3/4x) = 48
9x + 48 - 9x = 48
9x - 9x + 48 = 48
0x + 48 = 48
-48 -48
0x = 0
0 0
x = 0
9(0) + 12y = 48
0 + 12y = 48
12y = 48
12 12
y = 4
(x, y) = (0, 4)