## Expressions and Equations

## Formative Assessment

# Summary of the Math: Expressions and Equations

**Read and Discuss**

An expression can combine arithmetic operations with numbers, letters, or both. Letters are used to represent variables.

- To evaluate an expression, find the value of the expression by replacing each variable in the expression with a given number.
- Two expressions are equivalent if they represent the same amount. When a given value is substituted for each variable (such as
*x*), equivalent expressions have the same value. - An equation is a statement that two expressions are equal. Every equation is composed of two expressions linked by an equal sign.
- To solve an equation, find the value of the variable that makes the two sides of the equation equal.

## Hint:

Can you:

- Describe the differences between an expression and an equation?
- Explain what it means to evaluate an expression?
- Explain what it means to solve an equation?
- Explain what it means for expressions to be equivalent?