Evaluate Expressions Intro

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 in mathematics?

Back

The order of operations is a set of rules that dictates 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

How do you represent multiplication in an expression?

Back

Multiplication can be represented using the symbol '×', a dot (·), or by placing numbers next to each other (e.g., 3x means 3 times x).

Front

What is the expression for the total number of cars in a parking lot with 6 rows and 15 cars per row, after 3 cars leave?

Back

The expression is @(6 \times 15) - 3@.

Front

If you have an expression like 1 + 4 + 9 × 2, how do you evaluate it?

Back

You first perform the multiplication: 9 × 2 = 18, then add: 1 + 4 + 18 = 23.

Front

What is the value of the expression @(15 - 6)@?

Back

The value is 9.

Front

How do you simplify the expression @(3 \times (15 - 6))@?

Back

First, evaluate the parentheses: 15 - 6 = 9, then multiply: 3 × 9 = 27.

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.

Front

What does it mean to let a number go in a word problem?

Back

To let a number go means to subtract that number from the total.