Lesson 1.9 : Equations with Negative Coefficients

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Lesson 1.9 Equations with Negative Coefficients

• Standards AF 1.1 and AF 4.1
• Objective Solve equations that have negative
  coefficients

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Coefficient

• A coefficient is the number in front of the
  variable
• 4x
• A negative coefficient is the negative number in
  front of the variable
• -x , -2x, -9h, -20b

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Objective - To solve equations involving negative
coefficients.
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Solve.
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Jerry made a profit of 320 selling snack bars at
a bike race. If the total sales were 1000 and
the snack bars cost him 2 each, how many did he
sell?
Profit Income - Expenses
320

1000
- 2x
-1000 -1000
-680 -2x
-2 -2
He sold 340 snack bars.
340 x
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Solve.
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The population in Falls Creek was 34,000
this year. If the population decreases at 1250
people per year, in how many years will the
population be 14,000?
Let x of years
34,000
- 1250x

14,000
-34,000 -34,000
- 1250x -20,000
- 1250 -1250
x 20
In 20 years
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Instructional Conversation

• You are going to partner up with the person next
  to you.
• You are going to solve each problem, then talk
  about each problem using the vocabulary. The idea
  is to be great at using the vocabulary correctly.
• The text is SOLVING EQUATIONS.

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Problem 1

• 4x 5x 10 35

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Problem 2

• 12x 5 3x 14

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Problem 3

• -5x 5 30

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Problem 4

• 3 x -2