6.AT.7 Group 1 · Extra Support

Practice Set · Part 1

Simplify Algebraic Expressions

Pick up where we left off

Name: Date: Group:

Where we left off

Our goal: With my small group, I can simplify algebraic expressions by combining like terms — one step at a time, with support.

The big idea: Like terms have the same variable, so add their coefficients and keep the variable the same.

Model to copy — Example 1 · Add like items

  1. Three rooms need microphones and stands. They need (4 + 2 + 6) microphones and (3 + 5 + 1) stands. How many of each do they need?
  2. Add the microphones: 4 + 2 + 6 = 12
  3. Add the stands: 3 + 5 + 1 = 9
  4. They need 12 microphones and 9 stands.
  5. Let m stand for microphones and s stand for stands. Simplify 4m + 2m + 6m + 3s + 5s + 1s.
  6. Group the like terms: (4m + 2m + 6m) + (3s + 5s + 1s)
  7. Add the coefficients of the m terms: 4 + 2 + 6 = 12 → 12m
  8. Add the coefficients of the s terms: 3 + 5 + 1 = 9 → 9s
  9. The simplified expression is 12m + 9s.

Start here

You did these with your group. Now do them on your own — the model above is yours to copy.

  1. 1

    Same stepsFinish what the group started. Use the model above, step for step.

    Let's do one together: Simplify 5x + 3x. Are 5x and 3x like terms? How do you know? (Yes. Both terms have the variable x.) Add the coefficients. (5 + 3 = 8) Write the simplified expression. (8x)

    My first step is ___ , because the problem asks for ___ .

    Show your work
  2. 2

    Warm restartExpand 5(x + 3).

    1. A5x + 15
    2. B5x + 3
    3. C8x
    4. Dx + 15
  3. 3

    Warm restartWhich shows 6n + 18 factored using its GREATEST common factor?

    1. A2(3n + 9)
    2. B3(2n + 6)
    3. C6(n + 3)
    4. D6(n + 18)
  4. 4

    Warm restartExpand 4(2y − 5).

    1. A2y − 20
    2. B6y − 20
    3. C8y − 20
    4. D8y − 5
6.15 Small Group · Group 1 · Practice SetPart 1 of 4
6.AT.7 Group 1 · Extra Support

Practice Set · Part 2

Simplify Algebraic Expressions

Keep going

You answered these out loud. Now write them.

Answer, then say how you know — the reason is the part that counts.

  1. 5

    Think it throughSimplify (8m + 5) + (3m + 7) + (4m + 2).

    1. A12m + 17
    2. B15m + 14
    3. C15m + 15
    4. D29m

    Why is that the answer?

    I chose ___ because ___ .

  2. 6

    Think it throughWhat does the 15m tell the festival?

    1. A15 cables are needed for every microphone
    2. BThere are 15 microphones
    3. C15 stages need cables
    4. DThe cables cost $15

    How do you know?

    I chose ___ because ___ .

  3. 7

    Think it throughIf each stage has 4 microphones (m = 4), how many cables in total?

    1. A29
    2. B60
    3. C64
    4. D74

    Explain your thinking.

    I chose ___ because ___ .

  4. 8

    Back to the modelWhat rule determines whether two terms are 'like terms'? Why can't you combine unlike terms?

    Two terms are like terms when they have the same ___. You cannot combine ___ and ___ because they represent different ___.

6.15 Small Group · Group 1 · Practice SetPart 2 of 4
6.AT.7 Group 1 · Extra Support

Practice Set · Part 3

Simplify Algebraic Expressions

Words and reasoning

Word bank · Banco de palabras

Like Terms (Términos semejantes)Combine (Combinar)Simplify (Simplificar)Coefficient (Coeficiente)Term (Término)Distributive property (Propiedad distributiva)

Use the words

Fill each blank with a word from the bank.

Explain the thinking

  1. 9

    Find the mistakeAnother student made this exact mistake in this lesson. Explain why it is wrong, then write what they should have done.

    The mistake: A common mistake in Simplify Algebraic Expressions is sweeping a constant into the variable terms — for example, simplifying 6x + 4 + 2x as 12x by adding all three numbers (6 + 4 + 2 = 12) instead of recognizing that 4 has no variable and cannot combine with 6x and 2x.
  2. 10

    Say moreTo simplify 6x + 4 + 2x + 7, which are the like terms, and how do you combine them?

    The like terms are ___ and ___.

  3. 11

    Change one numberGo back to Part 1 and pick one problem you already solved. Change one number in it, then solve your new version. Show every step.

    If ___ changed to ___ , then ___ .

    Show your work
6.15 Small Group · Group 1 · Practice SetPart 3 of 4
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Practice Set · Part 4

Simplify Algebraic Expressions

Show what you know

Last check

These two come from Lesson 6.14. If they are shaky, that is the lesson to revisit — not this one.

  1. 12

    Show what you knowQuick check — you've got this: Simplify 6x + 3 + 2x + 5.

    1. A8x + 8
    2. B8x² + 8
    3. C16x
    4. D62x + 35

    Explain your choice.

    I know it is ___ because ___ .

  2. 13

    From Lesson 6.14Quick check — you've got this: Which expression is equivalent to 7(x + 3)?

    1. A7x + 21
    2. B7x + 3
    3. C7x + 10
    4. Dx + 21
  3. 14

    From Lesson 6.14A student wrote 8(12 + 9) = 8 × 12 + 9 = 105. What went wrong?

    1. AThey added instead of multiplying
    2. BThey used the wrong prices
    3. CThey forgot to multiply the 9 by 8 as well
    4. DThey distributed too many times

Be honest — this tells your teacher what to do next

I can…Not yetGetting thereGot it
I can simplify algebraic expressions by combining like terms — one step at a time, with support.
I can explain why it works: Like terms have the same variable, so add their coefficients and keep the variable the same.
I can talk through each step out loud using a sentence frame and the lesson's key words.

One question I want to ask my group next time