Answer:
x = 55 - 2y
y = 70 - 3x
x = 17
y = 19
Step-by-step explanation:
let x = small box
y = large box
6x + 12y = 330
12x + 4y = 280
6x + 12y = 330
6x = 330 -12y
6x/6 = (330-12y)/6
x = 55 - 2y
12x + 4y = 280
4y = 280 -12x
4y/4 = (280 -12x)/4
y = 70 - 3x
small box cost:
x = 55 - 2y
x = 55 - 2(70-3x)
x = 55 -140 + 6x
x - 6x = -85
-5x = -85
x = 17
large box
y = 70 - 3x
y = 70 - 3(17)
y = 70 - 51
y = 19