equivalent equations.notebook
Review
Writing variable expressions to represent word problems
Create a situation for each expression: ﴾a﴿ p – 3 ﴾b﴿ 3 – p
* Explain how the position of the variable changes the meaning of the expression in each case.
* Would this also apply to the following expressions? ﴾a﴿ p + 3 ﴾b﴿ 3 + p 1
equivalent equations.notebook
Match each of the following situations with the correct expression:
Harry is twice as old as Noel 4n + 2
Susan has a bag of candy and gave away four 2n
Margot has four packages of hockey cards and two individual cards n + 2
Harry is two years older than Noel 4 – n Susan has 4 dolls and gives some away n – 4 2
equivalent equations.notebook
Exit Card Activity
Write an algebraic expression to represent each pattern rule below:
a﴿ Double a number
b﴿ Five more than a number
c﴿ Three less than a number
d﴿ A number less than ten
e﴿ Six more than twice a number
f﴿ One less than triple a number 3
equivalent equations.notebook
Equivalent
Equations
Algebra Balance Scales
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equivalent equations.notebook
Creating Equivalent Equations using Addition
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equivalent equations.notebook
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equivalent equations.notebook
Creating Equivalent Equations using Addition
Equation: n + 2 = 5
Equation: How did you create your equivalent equation?
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equivalent equations.notebook
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Creating Equivalent Equations using Addition
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1. Copy the above balance scale into your notebook. Write the equation to represent the objects on this balance scale.
2. Create an equivalent equation by copying the above balance scale, then adding constant amounts to each side of it. Write the equivalent equation underneath the balance scale.
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equivalent equations.notebook
Creating Equivalent Equations
Using Subtraction
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equivalent equations.notebook
In order for equations to be equivalent, the same operations have to be performed on each side where the value of the variable does not change. E.g., 3n + 1 = 7 and 3n = 6 are equivalent equations because 1 is subtracted from each side in the first equation to make the second equation. This is called ‘preservation of equality’.
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equivalent equations.notebook
Creating Equivalent Equations using Subtraction
Equation: n + 2 = 5
Equation: How did you create your equivalent equation?
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equivalent equations.notebook
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creat
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t
n
ur tur quations!
o
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alent
v
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Creating Equivalent Equations using Subtraction
n
1. Copy the above balance scale into your notebook. Write the equation to represent the objects on this balance scale.
2. Create an equivalent equation by copying the above balance scale, then subtracting constant amounts to each side of it. Write the equivalent equation underneath the balance scale.
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equivalent equations.notebook
Creating Equivalent Equations using Multiplication
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equivalent equations.notebook
Creating Equivalent Equations using Multiplication
Equation: n + 4 = 6
Equation: How did you create your equivalent equation?
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equivalent equations.notebook
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creat
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ur tur quations!
o
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'
t
I
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alent
v
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Creating Equivalent Equations using Multiplication
1. Copy the above balance scale into your notebook. Write the equation to represent the objects on this balance scale.
2. Create an equivalent equation by copying the above balance scale, then subtracting constant amounts to each side of it. Write the equivalent equation underneath the balance scale.
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equivalent equations.notebook
Creating Equivalent Equations using Division
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equivalent equations.notebook
Creating Equivalent Equations using Division
Equation: 2n + 4 = 8
Equation: How did you create your equivalent equation?
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equivalent equations.notebook
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Creating Equivalent Equations using Division
1. Copy the above balance scale into your notebook. Write the equation to represent the objects on this balance scale.
2. Create an equivalent equation by copying the above balance scale, then subtracting constant amounts to each side of it. Write the equivalent equation underneath the balance scale.
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equivalent equations.notebook
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