Problem 3

Question

Use a commutative property to complete each statement. See Examples 1 and 3. $$ -4 \cdot y= $$

Step-by-Step Solution

Verified
Answer
The completed expression is \(y \cdot (-4)\).
1Step 1: Identify Commutative Property in Use
The commutative property of multiplication states that changing the order of the factors does not change the product. In mathematical terms, this is expressed as: \[a \times b = b \times a\] We will apply this property to the given expression \(-4 \cdot y\).
2Step 2: Apply the Commutative Property
Using the commutative property, we switch the order of multiplication in the expression. The expression \(-4 \cdot y\) becomes \(y \cdot (-4)\).
3Step 3: Write the Completed Expression
The completed expression, after applying the commutative property, is \[y \cdot (-4)\]

Key Concepts

MultiplicationAlgebraMathematical Properties
Multiplication
Multiplication is one of the basic operations in mathematics, alongside addition, subtraction, and division. When you multiply, you are essentially adding a number to itself a certain number of times. For example, multiplying 4 and 3 means you are adding 4 three times: 4 + 4 + 4, which equals 12.
In expressions, multiplication is represented by symbols such as \(\times\) or \(\cdot\). These symbols tell you that two numbers, called factors, need to be multiplied together to reach a product. Factors can be numbers, variables like \(x\), or a combination of both. Understanding how multiplication connects to other concepts is vital in solving mathematical equations effectively.
Algebra
Algebra is a branch of mathematics that uses symbols and letters to represent numbers and quantities in formulas and equations. It is a powerful tool that allows us to solve problems ranging from everyday calculations to complex scientific queries. In algebra, equations like \( -4 \cdot y = ?\) allow you to determine the value of unknown variables, given certain conditions.
A fundamental skill in algebra is manipulating these equations to isolate variables, like y in the given exercise. Using algebraic properties such as the commutative property can simplify and solve these equations. In this example, rearranging the expression using the commutative property shows that no matter how we order \(-4\) and \(y\), the multiplication outcome remains unchanged. This concept helps us understand the flexibility and utility of algebraic manipulation.
Mathematical Properties
Mathematical properties are rules that govern arithmetic operations and help simplify and solve expressions. These include properties like associative, distributive, and commutative properties. The commutative property, in particular, indicates that the order of numbers does not affect the final result when performing operations such as addition or multiplication.
For example, with multiplication, if you have \(a \times b\), it will always equal to \(b \times a\). This property simplifies calculations and shows the interchangeable nature of factors. In our given exercise, this property allowed us to neatly rearrange \(-4 \cdot y\) into \(y \cdot (-4)\) without changing the product. This is especially helpful in algebra for reorganizing expressions to make them easier to understand and solve.