Last updated at February 10, 2026 by Teachoo
Transcript
Expression, Equation, AlgebraLet’s look into them in detail EXPRESSION (The Phrase) What it is: A group of numbers, symbols, and letters. The Rule: It has NO equals sign (=). Example: 3x + 5 English comparison: Like saying "The red car..." (It’s just a description, not a full thought). EQUATION (The Sentence) What it is: Two expressions set equal to each other. The Rule: It MUST have an equals sign (=). Example: 3x + 5 = 20 English comparison: Like saying "The red car is fast." (Now it’s a complete fact). ALGEBRA (The Detective Work) What it is: The branch of math used to solve the puzzle. The Goal: Using math rules to get the letter (x) by itself to find the mystery number. Example: Solving the equation to discover that x = 5. In this chapter, we do Algebra A mathematical phrase (no equals sign). A statement that two expressions are equal. The branch of math that uses variables to solve problems.