Letters in Math?

In algebra, we do math with letters, known as “variables.” Variables take the place of numbers—so you can substitute a number for a variable to find an answer. This lets us use the same equation or expression for different situations or problems. An expression is a statement that uses variables. It does not use an equal sign. For example, 2x+5 is an expression. An equation is a statement using variables that does use an equal sign. For example, 2x+5=17 is an equation. Use this VLE to explore both expressions and equations!

Videos about Algebraic Equations and Expressions:

Writing Algebraic Expressions for Situations

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NSF logo This material is based upon work supported by the National Science Foundation under Grant No. DUE-0840824. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.