6.5 · Part II
Supported Application · Guided Entry to Today's Problem
Write Algebraic Expressions · Variable
- Define the variable to represent the unknown quantity
- Translate mathematical phrases into operations, coefficients, and constants
- Evaluate by substituting given numerical values for the variable
- Write Algebraic Expressions (Escribir expresiones algebraicas) — Translate words or a situation into numbers, variables, and operation symbols.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Algebraic Expression (Expresión algebraica) — A math phrase that has at least one letter.
- Coefficient (Coeficiente) — The number in front of a letter, like the 3 in 3x.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- Like terms (Términos semejantes) — Terms with the same letter raised to the same power, like 2x and 5x.
- A common mistake in Write Algebraic Expressions is treating 'each' or 'per' as if it means add instead of multiply, and attaching the variable to the wrong number. For 'a $25 setup fee plus $8 per hour, h,' students often write 25 + 8 + h (adding all three numbers) or 25h + 8 (multiplying the flat fee by h) instead of the correct 8h + 25. Since $8 applies per hour, it must multiply the variable (8h), and the flat $25 fee is a constant added only once — check that the per-unit rate, not the flat fee, is the number multiplied by the variable.
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1 MULTIPLE CHOICE
Evaluate 4.25s + 23.50 when s = 10.
- A$66.00
- B$277.50
- C$47.75
- D$66.75
My work — one step per line What I did to both sides - 1LookWhat is done to the variable?
- 2UndoDo the opposite — both sides.
- 3SimplifyOne side at a time.
- 4CheckPut it back in.
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2 MULTIPLE CHOICE
Which key word tells you to multiply?
- AProduct
- BSum
- CDifference
- DQuotient
✏️ Workspace & Solution Steps -
3 MULTIPLE CHOICE
(Lesson 6.3) What is the value of 4³?
- A64
- B12
- C43
- D7
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.
6.5 · Part II
On-Level Application · Standard Rigor
Write Algebraic Expressions · Variable
- Define the variable to represent the unknown quantity
- Translate mathematical phrases into operations, coefficients, and constants
- Evaluate by substituting given numerical values for the variable
- Write Algebraic Expressions (Escribir expresiones algebraicas) — Translate words or a situation into numbers, variables, and operation symbols.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Algebraic Expression (Expresión algebraica) — A math phrase that has at least one letter.
- Coefficient (Coeficiente) — The number in front of a letter, like the 3 in 3x.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- Like terms (Términos semejantes) — Terms with the same letter raised to the same power, like 2x and 5x.
- A common mistake in Write Algebraic Expressions is treating 'each' or 'per' as if it means add instead of multiply, and attaching the variable to the wrong number. For 'a $25 setup fee plus $8 per hour, h,' students often write 25 + 8 + h (adding all three numbers) or 25h + 8 (multiplying the flat fee by h) instead of the correct 8h + 25. Since $8 applies per hour, it must multiply the variable (8h), and the flat $25 fee is a constant added only once — check that the per-unit rate, not the flat fee, is the number multiplied by the variable.
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1 MULTIPLE CHOICE
Line 1: A lyric says '7 more than a number of beats n.' Which expression matches?
- An + 7
- B7n
- Cn − 7
- D7 − n
✏️ Workspace & Solution Steps -
2 MULTIPLE CHOICE
Line 2: The chorus says '5 less than a number of tracks x.' Which expression matches?
- Ax − 5
- B5 − x
- C5x
- Dx + 5
✏️ Workspace & Solution Steps
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3 MULTIPLE CHOICE
The expression 8n + 15 gives the cost of n tickets plus a fee. What is the cost for 6 tickets?
- A$63
- B$138
- C$29
- D$48
My work — one step per line What I did to both sides
Writing Task: Justify why your mathematical solution is accurate and complete.
6.5 · Part II
Extension & Non-Routine Application
Write Algebraic Expressions · Variable
- Define the variable to represent the unknown quantity
- Translate mathematical phrases into operations, coefficients, and constants
- Evaluate by substituting given numerical values for the variable
- Write Algebraic Expressions (Escribir expresiones algebraicas) — Translate words or a situation into numbers, variables, and operation symbols.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Algebraic Expression (Expresión algebraica) — A math phrase that has at least one letter.
- Coefficient (Coeficiente) — The number in front of a letter, like the 3 in 3x.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- Like terms (Términos semejantes) — Terms with the same letter raised to the same power, like 2x and 5x.
- A common mistake in Write Algebraic Expressions is treating 'each' or 'per' as if it means add instead of multiply, and attaching the variable to the wrong number. For 'a $25 setup fee plus $8 per hour, h,' students often write 25 + 8 + h (adding all three numbers) or 25h + 8 (multiplying the flat fee by h) instead of the correct 8h + 25. Since $8 applies per hour, it must multiply the variable (8h), and the flat $25 fee is a constant added only once — check that the per-unit rate, not the flat fee, is the number multiplied by the variable.
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1 MULTIPLE CHOICE
A concert ticket costs 8 dollars. The website also charges one 5 dollar service fee for the whole order. Let t represent the number of tickets bought in one order. Which expression gives the total cost in dollars?
- A8t + 5
- B8 + 5t
- C8(t + 5)
- D13t
✏️ Workspace & Solution Steps
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2 OPEN RESPONSE
Field day needs one $4.25 item per student plus a one-time $23.50 shipping fee. Write the expression, then find the cost for 30 students AND for 60 students. Does doubling the students double the cost? Explain.
✏️ Mathematical Justification & Response -
3 OPEN RESPONSE
Write a real-world situation that could be modeled by the expression 4n + 10. Explain what the variable n represents, what the coefficient 4 means, and what the constant 10 represents.
✏️ Mathematical Justification & Response
Writing Task: Justify why your mathematical solution is accurate and complete.