1. ALGEBRA SUPPORT (Homework)
MS Algebra A-F-IF-7 – Ch. 7.3a Solve Linear Systems by Elimination through Addition or Subtraction
ALGEBRA SUPPORT (Homework)
Solve Linear Systems by Elimination through Addition or Subtraction

2. SUPPORT Learning Target
Title: 7.3a Solve Linear Systems by Elimination with Addition/Subtraction
Date:
SUPPORT Learning Target
By the end of the period, I will solve linear systems by elimination with addition or subtraction.
I will demonstrate this by completing Four-Square Notes and by solving problems in a pair/group activity.

3. Home Work 1-2-3: 1) Class 4-Square Notes Put In Binder?
2) Section 7.3 Pg ) Section ______
TxtBk.Prob.#5,7,9,13,17,19 Notes Copied on blank sheet Solved and Put in Binder? of paper in Binder?
Table of Contents
Date Description Date Due

4. Solving Systems by Elimination
Notes:
Step 1: Add or subtract the equations to eliminate one variable.
Step 2: Solve the resulting equation for the other variable.
Here we choose to ADD the two equations.
Here we solve for x.
Eq. 1: x – y = 5
Eq. 2: + 3x + y = 3
4x = 8
4x = 8
4 4
x = 2
Step 3: Substitute in either original equation to find the value of the eliminated variable.
Eq. 1: (2) – y = 5
- y = 3
y = -3
Step 4: Check your solution
Solution:
(2,-3)
Equation 1: 2 – (-3) = 5
Equation 2: 3(2)+(-3)=3

5. ( , ) 9x + y = 2 +(-4x – y = -17) Solution: Solve the linear system.
HW # 5
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
STEP 3
9x + y = 2
Equation 1
+(-4x – y = -17)
Equation 2
STEP 1
STEP 2
Solution:
( , )
STEP 4

6. ( , ) -9x + 4y = -17 +(9x – 6y = 3) Solution: Solve the linear system.
HW # 7
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
STEP 3
-9x + 4y = -17
Equation 1
+(9x – 6y = 3)
Equation 2
STEP 1
STEP 2
Solution:
( , )
STEP 4

7. ( , ) 2x + 5y = 31 +(-2x + y = -1) Solution: Solve the linear system.
HW # 9
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
STEP 3
2x + 5y = 31
Equation 1
+(-2x + y = -1)
Equation 2
STEP 1
STEP 2
Solution:
( , )
STEP 4

8. Storm Check (Think, Write, Discuss, Report)
Explain in your own words the four steps of solving systems of equations by Elimination?
The four steps of solving systems of equations by elimination are:
1) _________________________________________
2) _________________________________________
3) _________________________________________
4) _________________________________________

9. - ( , ) x – y = -4 (x + 3y = 4) Solution: Solve the linear system.
HW # 13
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
x – y = -4 -
Equation 1
(x + 3y = 4)
Equation 2
Solution:
( , )

10. - ( , ) 4x – 9y = -21 (4x + 3y = -9) Solution:
HW # 17
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
4x – 9y = -21 -
Equation 1
(4x + 3y = -9)
Equation 2
Solution:
( , )

11. - ( , ) 6x – y = -1 (6x – 3y = -27) Solution: Solve the linear system.
HW # 19
Solve the linear system.
Use the Elimination method
STEP 1 Add or Subtract the Equations
STEP 2 Solve the resulting Equation for the Remaining Variable
STEP 3 Substitute in either original equation to find the value of the eliminated variable.
STEP 4 Check Solution
6x – y = -1 -
Equation 1
(6x – 3y = -27)
Equation 2
Solution:
( , )

12. Vocabulary System of Linear Equations
Solution to a System of Equations
Solve by Graphing
Solve by Elimination
Solve by Substitution

13. Vocabulary Acquisition
Friendly Definition
Sketch
Wordwork
Sentence
DAY 2
1. Review word
Friendly Definition
Physical Representation
2. Draw a sketch
DAY 1
Use Visuals
Introduce the word
Friendly Definition
Physical Representation
Use Cognates
Write friendly definition
Word List
Vocabulary Acquisition
DAY 3 and/or DAY 4
1. Review the word
Friendly Definition
Physical Representation
2. Show how the word works
Synonyms/antonym
Word Problems
Related words/phrases
Example/non-example
DAY 5
1. Review the word
Friendly definition
Physical Representation
3. Write a sentence
at least 2 rich words (1 action)
correct spelling
correct punctuation
correct subject/predicate agreement
clear and clean writing

14. Storm Check (Think, Write, Discuss, Report)
To verify your solution to a system of linear equations, what do you have to do?
To verify my solution to a system of linear
equations, I have to _________________________
___________________________________________
___________________________________________.