quiz 3

In problems 1,2 show steps of solutions. Problems 3,4,5,6 require graphs. Sketch graphs on paper and submit them as a scan file of your handwriting.

1. For the matrix: perform following row operation: modify second row according to rule Row2 Row2 – 3Row1

(change second row to result of operation: Row2 – 3Row1)

2. Solve system of equations. Use any technique.

x + 2y = 1

2x + y = 8

3. What system of equations represents this augmented matrix?

Find solutions for x and y using any technique.

4. Office desk costs $260 and a chair costs $80. How many desks and how many chairs bought the company if total expenses were $2,260? Create system of two equations with x and y and show solution.

5. Solve the linear inequality graphically (show graph of border line and shade the portion that satisfy the inequality)

5x – 3y ≤ 15

6. Solve the linear inequality graphically (show graph of border line and shade the region that satisfy the inequality)

4x + y ≥ 4

7. Solve the system of two inequalities graphically

(graph each border line and shade the region that hold solution for both inequalities)

2x - 5y ≤ 10

x + y ≥ 5

8. Solve the system of inequalities graphically and find the coordinates of each corner point.

2x – y ≤ 2

2x + y ≥ – 2

Y ≤ 4