Solve Systems of Equations by Graphing

1
Solve Systems of Equations by Graphing

• Finding Intercepts

2
Solve a system graphically
EXAMPLE 1
Graph the linear system and estimate the
solution. Then check the solution algebraically.
4x y 8
Equation 1
2x 3y 18
Equation 2
-4x -4x y 8 4x
-2x -2x -3y 18 2x
-3 -3 y -6
x
SOLUTION
3
EXAMPLE 1
Solve a system graphically
Equation 2
Equation 1
4x y 8
2x 3y 18
The solution is (3, 4).
4
for Example 1
GUIDED PRACTICE
Graph the linear system and estimate the
solution. Then check the solution algebraically.
8x y 8
3x 2y 16
Equation 1
Equation 2
- 8x - 8x -y 8 8x -1
-1 y -8 8x
-3x -3x 2y -16 3x
2 2 y -8 - x
SOLUTION
5
for Example 1
GUIDED PRACTICE
Equation 1
Equation 2
8x y 8
3x 2y 16
The solution is (0, 8).
6
for Example 1
GUIDED PRACTICE
Graph the linear system and estimate the
solution. Then check the solution algebraically.
3x 2y 4
x 3y 1
Equation 2
Equation 1
y 1/3 1/3x
y -2 3/2x
SOLUTION
7
for Example 1
GUIDED PRACTICE
Equation 1
Equation 2
3x 2y 4
x 3y 1
The solution is (2, 1).