6­6 H (taught).notebook
Bell Ringer
1. 5x + y > 6
October 01, 2013
2. 2x ­ 2y ≥ 8
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6­6: Systems of Linear Inequalities
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System of Linear Inequalities
Two or more linear inequalities using the same variables.
SPI 3102.3.9 Solve systems of linear equations/inequalities in two variables.
Solution of a System of Linear Inequalities
Any ordered pair that makes ALL of the inequalities in the system true.
Ex. y < 5x + 7
y ≥ ­2x ­ 3
Example: Graph the system of inequalities.
y ≥ ­x + 5
Example: Graph the system of inequalities.
y > 3x ­ 2
­3x + y ≤ ­4
­2y ­ x ≤ 6
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6­6 H (taught).notebook
October 01, 2013
Your Turn: Graph the system of inequalities.
y ≥ ­x + 1
3x + y < 3
Example: Write a system of inequalities to represent the graph.
a.
b.
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Your Turn: Write a system of inequalities to represent the graph.
Example: Cherries cost $4/lb. Grapes cost $2.50/
lb. You can spend no more than $15 on fruit, and you need at least 4 lb in all. What is a graph showing the amount of each fruit you can buy?
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Your Turn: A dog walker earns $15 per hour. She also earns $12 per hour babysitting. She wants to earn at least $300 next week, but can work no more than 30 hours. What is a graph showing how many hours she can work at each job?
Homework
pgs. 399­401 (10­26 even, 39­42)
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