Expressions

An expression is a mathematical phrase that can contain numbers, variables, and operations. It represents a value and can be evaluated to obtain a numerical result.

Types of Expressions

There are several types of expressions:

• Numerical Expression: A mathematical expression that contains only numbers and operations. For example, 5 + 3 * 2.
• Variable Expression: An expression that contains variables, numbers, and operations. For example, 3x + 7.
• Algebraic Expression: A combination of variables, numbers, and operations. For example, 2x + 5y - 3.
• Complex Expression: An expression that contains multiple terms and operations. For example, (3x + 2) * (4y - 1).

Operations in Expressions

Common operations used in expressions include:

• Addition (+)
• Subtraction (-)
• Multiplication (*)
• Division (/)
• Exponents (^)

Evaluating Expressions

To evaluate an expression, you perform the operations according to the rules of arithmetic. For example, to evaluate the expression 3x + 7 when x = 2, you substitute the value of x and perform the operations: 3(2) + 7 = 6 + 7 = 13.

Examples

Here are some examples of expressions:

1. 2x + 5y - 3
2. (3a + 2b) * (4c - 1)
3. 5 + 3 * (8 - 2)

These examples illustrate the different types of expressions and the operations involved in evaluating them.