Writing Expressions from Words

Key idea

Translate phrases like “three more than twice a number” into algebra.

In depth

Translate phrases to symbols: sum means +, difference means −, product means ×, quotient means ÷. The order in words like less than or subtracted from is reversed.

Worked example

5 less than twice a number is 2n − 5, not 5 − 2n.

Formula

Real-world uses

• Turning a word problem about tickets or wages into an equation a calculator can solve

Common mistake

Reversing subtraction. Less than flips the order you read it in.

How to learn this

1. Read the key idea and say it in your own words.
2. Work through the worked example, then try a similar problem.
3. Use the interactive lesson’s visual and mini-quiz to check the pattern.

Frequently asked questions

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Related beginner topics in Algebra

• Variables and Expressions – Letters stand for unknown or changing numbers in expressions.
• Evaluating Expressions – Substitute values for variables and simplify.
• Like Terms – Terms with the same variable part can be combined.
• Distributive Property – Multiplication spreads over addition.
• Simplifying Expressions – Combine like terms and apply distribution to write expressions compactly.
• One-Step Equations – Undo one operation to isolate the variable.