Michael uses a blend of dark chocolate and milk chocolate to make the ice cream topping at his restaurant. He needs to buy
100

kg
100kg100, start text, k, g, end text of chocolate in total for his next order. Dark chocolate costs
$
12
$12dollar sign, 12 per kilogram, milk chocolate costs
$10dollar sign, 10 per kilogram, and he wants to spend
$1120dollar sign, 1120 total.
Let d be the number of kilograms of dark chocolate he buys and m be the number of kilograms of milk chocolate he buys.