CK-12-Pre-Calculus Concepts

(Marvins-Underground-K-12) #1

8.6. Augmented Matrices http://www.ck12.org


3 x+y=− 15
x+ 2 y= 15


  1. Use an augmented matrix to solve the following system.


−a+b−c= 0
2 a− 2 b− 3 c= 25
3 a− 4 b+ 3 c= 2

Answers:



  1. The row reduction steps are not shown. Only the initial and final augmented matrices are shown.



2 1 1


0 2 6


1 1 0


∣∣


∣∣


∣∣


16


0


10



→




1 0 0


0 1 0


0 0 1


∣∣


∣∣


∣∣


7


3


− 1




2.


[3 1


1 2


∣∣


∣∣−^15


15


]



[1 0


0 1


∣∣


∣∣−^9


12


]


3.




− 1 1 − 1


2 − 2 − 3


3 − 4 3


∣∣


∣∣


∣∣


0


25


2



→




1 0 0


0 1 0


0 0 1


∣∣


∣∣


∣∣


3


− 2


− 5




Practice


Solve the following systems of equations using augmented matrices. If one solution does not exist, explain why not.






4 x− 2 y=− 20
x− 3 y=− 15

2.


3 x+ 5 y= 33
−x− 2 y=− 13





x+ 4 y= 11
3 x+ 12 y= 33




Free download pdf