Section 3.6.notebook
January 06, 2011
Substitution and Elimination Method Review
Example 1:
x = 4y + 10
4x + 2y = 4
Example 2:
6x - 5y = 9
2x - y = 1
Substitution and Elimination Method Review
Example 1:
x = 4y + 10
4x + 2y = 4
Example 2:
6x - 5y = 9
2x - y = 1
Section 3.6.notebook
January 06, 2011
Section 3.6­­Three­Variable Systems
Objective:
To solve a system with 2 or more variables and equations.
Substitution Method
Example 1: Solve for the variables.
x + 5y - 6z = 29
y + 4z = -10
z = -3
Substitution Method
Example 2: Solve for the variables.
x - 2y + 3z = 9
y + 3z = 5
z=2
Section 3.6.notebook
January 06, 2011
Elimination Method
Example 3: Solve for all variables.
x - 2y + 3z = 9
-x + 3y
= -4
2x - 5y + 5z = 17
Elimination Method
Example 3: Solve for all variables.
x - 2y + 3z = 9
-x + 3y
= -4
2x - 5y + 5z = 17
Section 3.6.notebook
January 06, 2011
Elimination Method
Example 4: Solve for all variables.
x +y+z= 6
2x - y + z = 3
3x
-z=0
Elimination Method
Example 5: Solve for all variables.
x - 3y + z = 1
3x + y - 2z = -2
x - y- z= 1
Section 3.6.notebook
January 06, 2011
Elimination Method
Example 6: Solve for all variables.
x+ y+ z= 4
2x - y + 2z = 5
x - 2y - z = -3
Homework...
Section 3.6
Page 224
1, 4, 9, 15