Solving Linear Systems by Adding or Subtracting

Name ________________________________________ Date __________________ Class __________________ LESSON

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Solving Linear Systems by Adding or Subtracting Practice and Problem Solving: D

Which method is easier to use to solve the system of equations: substitution or addition/subtraction? The first one is done for you. 1.

y = 4y − 9 2x + 5y = 11

substitution ________________________

2. 4x − 3y = 6

3. 5x + 2y = 11

2x + 3y = 18

−3x + y = 0

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Solve each system of linear equations by adding or subtracting. Check your answer. The first one is done for you. 4.

2x − 5y = 4

5.

−2x + 8y = 8

3x − 4y = −4

(12, 4) ________________________________________

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6. 6x + y = 13

7. 10x − 4y = 2

3x + y = 4

9x + 4y = 17

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8.

x + 4y = 4

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7x − y = 9

9.

x − 2y = 8

7x + 2y = 24

−x + 2y = 13

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Write a system of equations to solve. The first one is started for you. 10. The sum of two numbers is 70. When the smaller number is subtracted from the bigger number, the result is 24. Find the numbers. x + y = 70; x − y = 24

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11. Two pairs of socks and a pair of slippers cost $30. Five pairs of socks and a pair of slippers cost $42. How much does a pair of socks cost? _________________________________________________________________________________________ Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.

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