1. Review
Find number of solutions using substitution or linear combinations. 2x – 6y = 5 3x – 9y = 2
Find number of solution using graphing. -2x + 5y = -18

2. 7.6 solving linear inequalities

3. Information
Linear inequality: 2 variables, replace = with inequality sign
<, >, ≤, ≥
If dividing by negative number, switches sign
2 Types of graphs
1. < or > = dotted graph
2. ≤ or ≥ = solid graph

4. Graph-t
y < 2 X ≥ -1 Y > x - 2

5. Graph-t
X + 2y ≥ -2 X + 2y ≤ 2

6. Graph-t
X – 2y ≥ 4 2x – y ≥ -2

7. Graph-st
2x + 2y ≥ -4 -2x – y ≥ 2

8. Graph-st
4x + 2y ≥ -6 8x + y < 3

9. Graph-st
X ≤ 0 Y ≥ 0 Y ≤ 5 X > -6

10. Write a system of linear inequalities that defines shaded region - T

11. Write a system of linear inequalities that defines shaded region - T

12. Write a system of linear inequalities that defines shaded region - sT

13. Write a system of linear inequalities that defines shaded region - sT

14. Wrap up Questions/Comments
Hw: text pg. 435, #’s: 9-14, evens, 30, 42