Solving Systems of Equations by Elimination with Addition and Subtraction

Use elimination to solve the system of equations.

3x – 2y = 24

x + 2y = 48

• x = 18

  y = 15

• x = -18

  y = -15

• x = -18

  y = 15

• x = 18

  y = -15

Choose a method that can be used to solve this system of equations by elimination.

2x – 2y = 24

4x + 7y = –40

• Subtract 2x from both equations and solve the first equation for y.

• Multiply the first equation by –2 and add the second equation.

• Add the first equation to the second equation and subtract 6x from both sides of the equation.

• Subtract 7y from the second equation and add the first equation.

What is the solution to the system of equations?

2x + 3y = 26

3x + 5y = 40

• x = 10, y = 2

• x = -10, y = -2

• x = -10, y = 2

• x = 10, y = -2

6x + 2y = 14

5x – 2y = 8

One way to solve this system of equations using elimination is to add the two equations to get 11x = 22. Then substitute 2 for x into either equation to get y = 1

• True

• False

• Both True and False

• I don't have a clue.

Sylvester and Lin go to the amusement park. Sylvester plays 5 rounds of mini golf and takes 4 turns in the batting cages for $60. Lin plays 3 rounds of mini golf and takes 6 turns in the batting cages for $45. Use two equations to find the price for each activity.

• Mini golf costs $10.00 per round.

  Batting cages cost $2.50 each turn.

• Mini golf costs $2.50 per round.

  Batting cages cost $10.00 each turn.

• Mini golf costs $9.00 per round.

  Batting cages cost $3.50 each turn.

• Mini golf costs $4.00 per round.

  Batting cages cost $6.50 each turn.

x - y = 11

2x + y = 19

• (10,-1)

• (-1,10)

• (3,-4)

• (6,7)

-6x + 5y = 1

6x + 4y = -10

• (1,-1)

• (0,-1)

• (1,1)

• (-1,-1)

-4x-2y=-12
4x+8y=-24

• (5,6)
• (6,-6)
• (6,-2)
• (4,-3)

4x+8y=20
-4x+2y=-30

• (-7,1)
• (2,-5)
• (-2,5)
• (7,-1)

Solve  the system of equations.  
   x + 5y = -27
-2x - 5y = 24

• (3, 6)
• (-3, -6)
• (-3, -4)
• (3, -6)