Solving Systems Problem Solving

Which method of solving would be the most efficient to solve the following system of equations?
2x - 5y = -6
-2x - 7y = 14

• Graphing

• Substitution

• Elimination

David is running a concession stand at a soccer game. He sells nachos and sodas. Nachos cost $1.50 each and sodas cost $0.50 each. At the end of the game, David made a total of $78.50 and sold a total of 87 nachos and sodas combined. Which system of equations represents this situation?

• 1.5x+0.5y=78.5
  x+y=87

• 1.5x+0.5y=78.5
  1.5x+0.5y=87

• x+y=78.5
  1.5x+0.5y=87

• x+y=78.5
  x+y=87

The talent show committee sold a total of 530 tickets in advance. Student tickets cost $3 each and the adult tickets cost $4 each. If the total receipts were $1740, how many of each type of ticket were sold?

• S + A = 530
  3S + 4A = 1740

• S + A = 530
  4S + 3A = 1740

• S + A = 1740
  3S + 4A = 530

• S + A = 1740
  4S + 3A = 530

John and Vicki are training for a 5km race.  John has already run 20 kilometers and plans to run 10 kilometers each day.  Vicki has already run 30 kilometers but plans to run only 5 kilometers per day. The graph below displays each of their training schedules. Which system of equations could be used to determine by which day both John and Vicki will have run the same amount in their training schedule?

• John: y = 20x + 10    Vicki: y = 30x + 5

• John: y = 10x + 20    Vicki: y = 30x + 5

• John: y = -10x + 20  Vicki: y = 5x + 30

• John: y = 10x + 20  Vicki: y = 5x + 30

Find the solution to the following pair of equations: 3x + 2y = 10 and 4x - y = 8

• x = 3, y = 5

• x = 1, y = 3

• x = 4, y = 6

• x = 2, y = 4

Find the solution to the following pair of equations: 3x + 2y = 10 and 4x - y = 8

• x = 3, y = 5

• x = 1, y = 3

• x = 4, y = 6

• x = 2, y = 4

What is the x coordinate of the solution to this system of equations? HINT: Graph and use nSolve. Menu 64.

Mathematical Equivalence

ON

Find the solution to the system of equations: 4x - 3y = 5 and 2x + 7y = 1

• x = 2, y = -1

• x = -1, y = 2

• x = 5, y = 3

• x = 3, y = 4

Find the solution to the system of equations: 4x - 3y = 5 and 2x + 7y = 1

• x = 2, y = -1

• x = -1, y = 2

• x = 5, y = 3

• x = 3, y = 4

Enter the x coordinate of the solution to this system of equations. HINT: Make sure both equations are in (x + y = #) form. Then do the shortcut.

Mathematical Equivalence

ON