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Andrew is working two summer jobs, making $14 per hour lifeguarding and making $10 per hour washing cars. In a given week, he can work at most 15 total hours and must earn no less than $170. Also, he must work at least 9 hours lifeguarding and at most 3 hours washing cars. If xx represents the number of hours lifeguarding and yy represents the number of hours washing cars, write and solve a system of inequalities graphically and determine one possible solution.

User Morgen
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Answer:

One possible solution that satisfies all the conditions is Andrew working 9 hours lifeguarding and 6 hours washing cars.

Step-by-step explanation:

Andrew's situation can be represented by the following system of inequalities:

Let x represent the number of hours lifeguarding and y represent the number of hours washing cars.

The inequalities can be written as:

1. x ≥ 9 (He must work at least 9 hours lifeguarding)

2. y ≤ 3 (He can work at most 3 hours washing cars)

3. x + y ≤ 15 (He can work at most 15 total hours)

4. 14x + 10y ≥ 170 (He must earn no less than $170)

Now let's graph these inequalities to find a possible solution:

  • First, graph the line x = 9 (vertical line passing through x = 9).
  • Then graph the line y = 3 (horizontal line passing through y = 3).
  • Next, graph the line x + y = 15 (diagonal line where x + y equals 15).
  • Finally, graph the line 14x + 10y = 170 (the line representing earnings of at least $170).

The intersection of these shaded regions represents the feasible area where all conditions are satisfied.

From the graph, the feasible region appears to be a triangular area. The vertices of the feasible region are the points where the lines intersect:

- (9, 3)

- (9, 6)

- (11, 4)

Let's check one of these points to determine a possible solution. Let's take (9, 6):

- Lifeguarding hours (x): 9 hours

- Washing cars hours (y): 6 hours

Total hours worked: x + y = 9 + 6 = 15 (within the limit)

Earnings: 14x + 10y = 14(9) + 10(6) = 126 + 60 = 186 (more than $170)

Therefore, one possible solution that satisfies all the conditions is Andrew working 9 hours lifeguarding and 6 hours washing cars.

User Sterls
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