Variable expressions are math phrases that include numbers, operations, and at least one variable (a letter that stands for an unknown number).
Variables are often represented by letters such as x, y, or n. Each letter can stand for a different number depending on the situation.
A variable is a symbol, usually a letter, that stands for a number we do not yet know. Variables help us write math ideas in general form instead of using only specific numbers.
Always substitute the variable with its given value before solving. This helps you find the numerical answer to the expression.
To write a variable expression, think about the relationship between numbers and the unknown quantity. Use words like “sum,” “difference,” or “quotient” to decide which operation to use.
Words like “sum,” “difference,” and “quotient” tell you which math operation to use.
To evaluate a variable expression, replace the variable with a given number and perform the operation to find the result.
Be careful to follow the correct order of operations when evaluating expressions that include more than one operation.
Variable expressions are important because they allow you to represent patterns, solve problems, and describe real-world situations mathematically.
Variables help you describe changing quantities and make general rules that work for many situations, not just one example.