Answer:
3 30 page printers, 10 70 page printers
Explanation:
x + y = 13
40x+70y = 820
Solving for y in first equation gives: y = 13 - x
Plug into second equation: 40x + 70(13 - x) = 820
40x + 910 - 70x = 820
-30 x = -90
x = 3
Plug into original equation: 3 + y = 13
y must = 10.
So, the company owns 3 thirty page presses, and 10 70 page presses,