First, let the number of skis rented by x and the number of snowboards rented by y. We can then assemble the first equation from the amount of money made from the rentals.
44x + 58y = 2232
The second equation can come from the fact that 9 more skis were rented than snowboards.
y = x - 9
Therefore our system is:
44x + 58y = 2232
y = x - 9
