Answer:
y ≤ 20-8x
Explanation:
Darren needs to spend no more than 15 hours on cardio exercise (y). To figure out how much time he has we need to do 20-8x. Any leftover hours are the hours left for him to spend doing his exercises. Since y has to be less than or equal to 20-8x, the system of linear inequalities should be:
y ≤ 20-8x