Section B Section B Checkpoint

Problem 1

Andre says that 2x+52x + 5 and 7x7x are equivalent expressions because they have the same value when xx is 1. Do you agree with Andre’s reasoning? Explain your reasoning. Use a diagram if it helps.

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Solution
No, I do not agree. Sample reasoning: To be equivalent expressions, they need to have the same value for every value of the variable. When xx is 0, 2x+52x+5 is 5, but 7x7x is 0. Since they do not have the same value when xx is 0, they are not equivalent expressions.
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Sample Response
No, I do not agree. Sample reasoning: To be equivalent expressions, they need to have the same value for every value of the variable. When xx is 0, 2x+52x+5 is 5, but 7x7x is 0. Since they do not have the same value when xx is 0, they are not equivalent expressions.

Problem 2

Use the distributive property to write an expression that is equivalent to each expression.

  1. 3(x+4)3(x+4)

  2. a(3.5−2.7)a(3.5-2.7)

  3. 5y+105y+10

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Solution

Sample responses:

  1. 3x+123x+12
  2. 0.8a0.8a
  3. 5(y+2)5(y+2)
Show Sample Response
Sample Response

Sample responses:

  1. 3x+123x+12
  2. 0.8a0.8a
  3. 5(y+2)5(y+2)