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Systems of Linear Equations © G. Battaly, 2013 1 March 04, 2013 3.1 Systems of Linear Equations College Algebra Home Page Class Notes: Prof. G. Battaly, Westchester Community College, NY Study 3.1 # 1, 5, 13 Homework Problems online geogebra: Systems of 2 Linear Eq.

Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

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Page 1: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 1

March 04, 2013

3.1  Systems of Linear Equations

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Study 3.1 # 1, 5, 13

Homework Problems

on­line geogebra:Systems of 2 Linear Eq.

Page 2: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 2

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Given:     ­3x + y = 1

How many solutions? __________   

What about: A:        y  =  2x

                     B:  x ­ 3y  =  0

How many solutions? __________   

3.1  Systems of Linear Equations

Homework Problems

Page 3: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 3

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Is (1,2) a solution?  ______

What about: A:        y  =  2x                     B:  x ­ 3y  =  0How many solutions? __________   

3.1  Systems of Linear Equations

Homework Problems

Page 4: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 4

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Is (1,2) a solution?  ______

What about: A:        y  =  2x                     B:  x ­ 3y  =  0How many solutions? __________   

3.1  Systems of Linear Equations

Homework Problems

Substitute (1,2) in Eq. A:        A:        y  =  2x                    2  ?  2(1)               2  =  2  Yes.  (1,2) is a solution for eq. A 

Substitute (1,2) in Eq. B:        B:        x ­ 3y  = 0                   1 ­ 3(2) ? 0                    1 ­  6     0            ­5  =  0  NO.  (1,2) is NOT a solution for eq. B 

Page 5: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 5

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Is (1,2) a solution?  ______

What about: A:        y  =  2x                     B:  x ­ 3y  =  0How many solutions? __________   

3.1  Systems of Linear Equations

Homework Problems

   ­5  =  0  NO.  (1,2) is NOT a solution for eq. B 

Need points that are on both lines.Need (x,y) values that satisfy both equations.

Page 6: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 6

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

3.1  Systems of Linear Equations

Homework Problems

Solution             Type               Lines

   (x,y)           Independent      intersect

no points       Inconsistent       parallel

   line              Dependent         same

Solutions for a System of Linear Equations

Page 7: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 7

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

What is the solution?

A:        y  =  2xB:  x ­ 3y  =  0 

3.1  Systems of Linear Equations

Homework Problems

Page 8: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 8

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

3.1  Systems of Linear Equations

Homework Problems

y = 2x

x ­ 3y = 0

What is the solution?

(0,0)

A:        y  =  2xB:  x ­ 3y  =  0 

Page 9: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 9

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Find the solution.

A:  y  =   x ­ 5B:  y = ­2x + 4   

3.1  Systems of Linear Equations

Homework Problems

Page 10: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 10

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Find the solution.

A:  y  =   x ­ 5B:  y = ­2x + 4   

3.1  Systems of Linear Equations

Homework Problems

y = x ­ 5

y = ­2x + 4

(3, ­2)

Page 11: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 11

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Find the solution.

A:  20x ­ 8y = 16B:  ­15x + 6y = 18   

3.1  Systems of Linear Equations

Homework Problems

Page 12: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 12

March 04, 2013

­15x + 6y = 18

20x ­ 8y = 16

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

Find the solution.

A:  20x ­ 8y = 16B:  ­15x + 6y = 18   

3.1  Systems of Linear Equations

Homework Problems

Parallel Lines:Inconsistent SystemNo points of intersectionEqual slopes.Solution is empty set

Page 13: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 13

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

A:  2x ­ 3y = ­6B:    x + 3y = ­3   

3.1  Systems of Linear Equations

Homework Problems

on­line geogebra:Systems of 2 Linear Eq.

To find the solution, usethe link below.Enter the above equationsinto the input box belowthe graph.

Page 14: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 14

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

To find the solution, usethe link below.Enter the above equationsinto the input box belowthe graph.

A:  2x ­ 3y = ­6B:    x + 3y = ­3   

3.1  Systems of Linear Equations

Homework Problems

on­line geogebra:Systems of 2 Linear Eq.

Page 15: Study 3.1 # 1, 5, 13 - Battaly · Class Notes: Prof. G. Battaly, Westchester Community College, NY 3.1 Systems of Linear Equations Homework Problems Solution ... College Algebra Home

Systems of Linear Equations

© G. Battaly, 2013 15

March 04, 2013

College Algebra Home Page

Class Notes:  Prof. G. Battaly, Westchester Community College, NY

3.1  Systems of Linear Equations

Homework Problems

Solution             Type               Lines

   (x,y)           Independent      intersect

no points       Inconsistent       parallel

   line              Dependent         same

Solutions for a System of Linear Equations