1. Solve Linear Systems by Graphing
SECTION 3.1
Solve Linear Systems by Graphing

2. California Standard:
2.0: Students solve a system of two linear equations in two variables algebraically and are able to interpret the answer graphically. Students are able to solve a system of two linear inequalities in two variables and to sketch the solutions sets.

3. OBJECTIVE(S): By following instructions, students will be able to:
Identify the number of solutions of a linear system.

4. EXAMPLE 1:
Graph the system and determine the number of solutions

5. EXAMPLE 2:
Graph the system and determine the number of solutions

6. U-TRY #1:
Tell whether the linear system has no solution or infinitely many solutions. a) b)

7. NUMBER OF SOLUTIONS One Solution The lines intersect
The lines have different slopes.
Consistent, independent
No Solution
Parallel lines
SAME SLOPE, DIFFERENT y-intercepts
inconsistent
Infinitely Many Solutions
SAME LINE
SAME SLOPE and Y-INTERCEPTS
Consistent, dependent

8. EXAMPLE 4:
Without graphing the linear system, tell whether the linear system has one solution, no solution, or infinitely many solutions. a) b)

9. HOMEWORK
Sec 7.5 page 462 #5-13 ODD, ODD (Using the Properties learned in class)