1. Vocabulary: Chapter Section 6.3.1 Topic: Simultaneous Linear Equations
Simultaneous Linear Equations can be solved to find the point where two lines cross on an xy graph.

2. 2x 2x = 4 x = 2 3x + 4y = 16 x + 4y = 12 x + 4y = 12 3x + 4y = 16
Example One
Instructions:
Use elimination. Find the (x,y) coordinates where the lines cross.
3x + 4y = 16 x + 4y = 12
x + 4y = 12
3x + 4y = 16
(2) + 4y = 12
-( x + 4y = 12 ) 2x 4 -2 -2
2x = 4
4y = 10 ÷2 ÷2 ÷4 ÷4
x = 2
(2,10/4)
y = 10/4

3. Classwork One
Instructions: Solve the system of equations by using elimination.

4. 3( ) 5y 5y = 10 y = 2 x + 3y = 5 3x + 4y = 5 3x + 9y = 15 3x + 4y = 5
Example Two. Instructions: Use elimination. Find the (x,y) coordinates where the lines cross.
x + 3y = 5 3x + 4y = 5 3( )
3x + 9y = x + 4y = 5
3x + 4y = 5
3x + 9y = 15
-( 3x + 4y = 5 )
3x + 4(2) = 5
3x + 8 = 5 5y 10
5y = 10 -8 -8
3x = -3
y = 2
(2, -1)
x = -1

5. Classwork Two
Instructions: Solve the system of equations by using elimination.

6. Example Three Instructions: Use elimination
Example Three Instructions: Use elimination. Find the (x,y) coordinates where the lines cross.
2x + 3y = 5 3x + 2y = 5 3( ) 2( )
6x + 9y = x + 4y = 10
3x + 2y = 5
6x + 9y = 15
-( 6x + 4y = 10 )
3(1) + 2y = 5 5x
3 + 2y = 5 5
5x = 5 -3 -3
2y = 2 ÷5 ÷5
x = 1 ÷2 ÷2
(1,1)
y = 1

7. (3,-2) (-1,8) Classwork Three
Instructions: Solve the system of equations by using elimination.
(3,-2)
(-1,8)