Writing and Evaluating Expressions

Front

What is an expression in mathematics?

Back

An expression is a combination of numbers, variables, and operators (like +, -, ×, ÷) 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 variables and performing the operations.

Front

What is the order of operations?

Back

The order of operations is a set of rules that tells you the sequence to follow when evaluating an expression: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right). This is often remembered by the acronym PEMDAS.

Front

What is a numeric expression?

Back

A numeric expression is a mathematical phrase that includes numbers and operations but does not have an equal sign.

Front

How do you solve the expression 18 + (6 – 2) × 2?

Back

First, solve the parentheses: 6 - 2 = 4. Then multiply: 4 × 2 = 8. Finally, add: 18 + 8 = 26.

Front

What is the result of (10 + 33 - 3) ÷ 8?

Back

First, solve inside the parentheses: 10 + 33 - 3 = 40. Then divide: 40 ÷ 8 = 5.

Front

How do you solve the expression 18 − 4 × 2?

Back

First, multiply: 4 × 2 = 8. Then subtract: 18 - 8 = 10.

Front

What does 'two times the sum of eight and seven' mean in numeric expression?

Back

It means 2 × (8 + 7), which indicates you first add 8 and 7, then multiply the result by 2.

Front

How do you solve 7 x [32 - (3 x 4)]?

Back

First, solve inside the parentheses: 3 × 4 = 12. Then solve the brackets: 32 - 12 = 20. Finally, multiply: 7 × 20 = 140.

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 or equation.