expressions

Front

What is an expression in mathematics?

Back

An expression is a combination of numbers, variables, and operators (such as +, -, ×, ÷) that represents a value.

Front

What does it mean to evaluate an expression?

Back

To evaluate an expression means to calculate its value by substituting numbers for the variables and performing the operations.

Front

What is the order of operations?

Back

The order of operations is a set of rules that determines the sequence in which calculations are performed: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right), often abbreviated as PEMDAS.

Front

What is a numerical expression?

Back

A numerical expression is a mathematical phrase that includes numbers and operation symbols but does not have an equal sign.

Front

What is a variable in an expression?

Back

A variable is a symbol (often a letter) that represents an unknown value in an expression.

Front

How do you write the expression for 'the sum of a number x and 5'?

Back

The expression is written as: x + 5.

Front

What is the expression for 'twice the sum of 3 and 4'?

Back

The expression is written as: 2 × (3 + 4) or 2(3 + 4).

Front

What does it mean to simplify an expression?

Back

To simplify an expression means to reduce it to its simplest form by combining like terms and performing operations.

Front

What is the expression for 'the product of 6 and 7'?

Back

The expression is written as: 6 × 7 or 6(7).

Front

What is the expression for 'subtract 10 from the sum of 5 and 15'?

Back

The expression is written as: (5 + 15) - 10.