Definitions:

An algebraic expression is obtained by performing a finite number of the following operations on symbols representing numbers: addition, subtraction, multiplication, division or raising to the nth power.

A general example to help you recognize patterns and spot the information you're looking for

A mathematical expression can have variables as part of the expression. If x=3, and y=5, the expression $$7x + y - 4$$ becomes $$(7 * 3) + 5 - 4$$ which is equal to $$21 + 5 - 4$$ or $$22$$

We use them when we want to figure the out cost of multiple items.

Example: Solving Equations

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Variables and Expressions 1

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Evaluate a Formula Using Substitution

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Variables Expressions and Equations

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Examples of evaluating variable expressions

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Rearrange formulas to isolate specific variables

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