Final answer:
A system of linear inequalities that represents a student's work hours and earnings with two different jobs is 10x + 15y ≥ 120, x ≥ 8, and x + y ≤ 20, where x is the hours at the grocery store, and y is the hours teaching music.
Step-by-step explanation:
To represent the student's work situation using a system of linear inequalities with x as the hours worked at the grocery store and y as the hours teaching music lessons, we need to consider the following constraints:
The student earns $10 per hour at the grocery store: 10x.
The student earns $15 per hour teaching music lessons: 15y.
The student needs to earn at least $120 per week: 10x + 15y ≥ 120.
The student must work at least 8 hours per week at the grocery store, but not more than 20 hours in total each week: x ≥ 8 and x + y ≤ 20.
The system of linear inequalities that represents this situation is:
10x + 15y ≥ 120
x ≥ 8
x + y ≤ 20