Answer:the two equations that model the situation are
x + y = 48
3x + 2y = 15
Step-by-step explanation:
Let x represent the total number of hours that Derek worked.
Let y represent the total number of hours that Donnie worked.
Derek and Donnie mow 15 lawns over two 2 days. There are 24 hours in a day. Therefore, the number of hours in 2 days would be 2 × 24 = 48 hours. Therefore
x + y = 48 - - - - - - - - - -1
If Derek mows 3 lawns per hour and Donnie mows 2 lawns per hour, it means that
3x + 2y = 15 - - - - - - - - - 2