Algebraic Expressions: Translating Verbal Phrases

Algebraic Expressions

Definition of an Algebraic Expression

  • An algebraic expression is a mathematical phrase that can include numbers, variables, and operation symbols (such as +, -, *, /). It does not have an equality sign.

Task: Writing Algebraic Expressions

  • The exercise requires us to translate a verbal phrase into an algebraic expression.
Example Phrase: "Eighteen more than a number"
  • Unknown Variable Identification: Let the variable we are working with be denoted as x.

  • Translation: The phrase "Eighteen more than a number" can be interpreted as follows:

    • Step 1: Identify the unknown number, represented by x.
    • Step 2: Apply the phrase structure: "more than" indicates an addition operation. Therefore, we need to add 18 to the unknown number.
    • Final Algebraic Expression: The final expression becomes:

    extx+18ext{x} + 18

Additional Notes

  • The process of translating phrases into algebraic expressions often requires an understanding of key phrases indicating mathematical operations:

    • "more than" implies addition.
    • "less than" implies subtraction.
    • "times" or "product" implies multiplication.
    • "divided by" or "quotient" implies division.
  • Importance of Variables: Using variables (like x) is crucial in algebra to represent unknown quantities and formulate expressions that can be solved or manipulated mathematically.

  • Examples of similar phrases:

    • Twelve less than a number would be represented as: extx12ext{x} - 12
    • Three times a number would be represented as: 3imesextx3 imes ext{x} or 3extx3 ext{x}
  • Contextual Application: Understanding how to create algebraic expressions from verbal phrases is a foundational skill in algebra that applies to problem-solving in various contexts, including real-world applications such as calculating costs, determining quantities, and analyzing data.