Expressions

An expression in math is a combination of numbers, symbols, and operators (such as +, -, *, /) that represents a value. It can contain variables, constants, and mathematical operations.

Types of Expressions

There are different types of expressions:

1. Numerical Expression: A numerical expression contains only numbers and operations. For example, 5 + 3 * 2 is a numerical expression.
2. Variable Expression: A variable expression contains variables, numbers, and operations. For example, 2x + 3 is a variable expression, where x is the variable.
3. Algebraic Expression: An algebraic expression contains variables, numbers, and operations. For example, 3x + 2y - 5 is an algebraic expression, where x and y are variables.

Evaluating Expressions

To evaluate an expression means to find its value by performing the operations and substituting the variables with given values. For example, to evaluate the expression 2x + 3 when x = 4, you would substitute x with 4 and perform the operations to get the value.

Simplifying Expressions

Simplifying an expression involves combining like terms and performing the operations to reduce the expression to its simplest form. For example, simplifying the expression 3x + 2x - 5 would result in 5x - 5 after combining like terms.

Understanding expressions is important in math as they are used in various mathematical problems and equations.