Mon, 3/11 SWBAT

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Mon,
3/11SWBAT solve inequalities using addition,
subtraction, multiplication, division

• Agenda
• WU (5 min)
• Quiz (20 min)
• Inequalities charts (15 min)
• Solving inequalities adding and subtracting
  examples (10 min)
• Warm-Up
• Write your HW in your planner for next TWO weeks
• Take out HW1 / HW2 Absolute Value Functions
• HW3 Solving One-Step Inequalities

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Phrases for Inequalities Phrases for Inequalities Phrases for Inequalities Phrases for Inequalities
lt gt

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Phrases for Inequalities Phrases for Inequalities Phrases for Inequalities Phrases for Inequalities
lt gt
less than fewer than greater than more than less than or equal to at most no more than greater than or equal to at least no less than
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Endpoints (when graphing on a number line) Endpoints (when graphing on a number line) Endpoints (when graphing on a number line) Endpoints (when graphing on a number line)
lt gt

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Endpoints (when graphing on a number line) Endpoints (when graphing on a number line) Endpoints (when graphing on a number line) Endpoints (when graphing on a number line)
lt gt
Open Circle Open Circle Closed circle Closed circle
an open circle if you do NOT want to include the
end value, or
a closed circle if you do want to include the end
value
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• x 6 gt 10

x gt 4
x 6 10
x 4
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Interval Notation Interval Notation Interval Notation Interval Notation
lt gt
Parenthesis ( ) Parenthesis ( ) Bracket Bracket
Always use parenthesis with Infinity, 8
( ) a parenthesis if you do NOT want to include
the end value, or
a bracket if you do want to include the end
value.
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Interval Notation Interval Notation Interval Notation Interval Notation
lt gt
( ) ( )
Examples x gt 4 (4, 8 ) x 4 4, 8) x lt
1 (-8, 1)
Always use parenthesis with Infinity, 8
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Interval Notation Interval Notation Interval Notation Interval Notation
lt gt
( ) ( )
Always use parenthesis with Infinity, 8
Examples m lt 30 (-8, 30) x 3 3, 8) All
real numbers (-8, 8)
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• Solving and Graphing Inequalities by Addition
  and Subtraction

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• Ex 1 8n 7n 3
• Ex 2 22 gt m 8
• Ex 3 Three added to a number is no more than
  twice the number.

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WARNING!!!!! (Example 2 3)

• An equation such as x 5 can be written as 5 x
• (because of the Symmetric Property of Equality)
• You CANNOT rewrite an inequality such as 3 lt x as
  x lt 3
• The inequality sign always points to the lesser
  value (or its eati
• 3 lt x x gt 3

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• Solving and Graphing Inequalities by
  Multiplication and Division

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Very important.

• When you multiply or divide each side of an
  inequality by a negative number you always
  reverse or flip the inequality symbol.
• lt ? gt
• gt? lt
• ?
• ?

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RATIONALE

• 100 gt 3
• 100(-2) gt 3(-2)
• -200 gt -6

NOT TRUE! You must reverse the inequality
symbol -200 lt -6
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(No Transcript)
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Directions Solve the inequality, graph the
solution on a number line and write in interval
notation.

• Ex 1
• Ex 2
• Ex 3