Math Example: Language of Math--Variable Expressions--Multiplication and Subtraction--Example 23

Topic

Variable Expressions

Description

This example demonstrates the conversion of the verbal statement "Take away negative three times a number from eighteen" into the variable expression 3x + 18. It showcases how to interpret a complex sentence structure involving multiplication, subtraction, and negative numbers, and translate it into algebraic symbols, using x to represent "a number".

Variable expressions form the foundation of algebraic thinking, enabling the translation of real-world scenarios into mathematical language. This collection of examples guides students through the process of identifying key phrases that indicate specific operations and converting them into symbolic form. By engaging with these examples, students develop critical skills in mathematical interpretation and communication.

Encountering a variety of examples is crucial for students to fully comprehend the concept of variable expressions. Each example presents a unique scenario, challenging students to apply their understanding in different contexts. This diverse practice builds flexibility in thinking and reinforces the connection between verbal and symbolic representations of mathematical ideas.

Teacher Script: Excellent progress on this tricky example! Notice how "negative three times a number" translates to -3x. We're taking this away from eighteen, which gives us 18 - (-3x). Can you see why this simplifies to 3x + 18? Remember, subtracting a negative is the same as adding a positive. Try rephrasing this statement in your own words while keeping the same mathematical meaning. This practice will help you become more comfortable with different ways of expressing the same mathematical idea!

For a complete collection of math examples related to Variable Expressions click on this link: Math Examples: Variable Expressions: Multiplication and Subtraction Collection.