Rewriting Subtraction Expressions as Addition Expressions

Oct 13, 2025 by windailys.com 69 views

Directions: Find the Sum of Each New Expression

Rewriting Subtraction Expressions as Addition Expressions

In mathematics, subtraction is often represented as the opposite of addition. This means that instead of subtracting a number, we can add its negative counterpart. In this article, we will explore how to rewrite subtraction expressions as addition expressions and find the sum of each new expression.

Rewriting Subtraction Expressions as Addition Expressions

To rewrite a subtraction expression as an addition expression, we need to follow a simple rule: subtraction is the opposite of addition. This means that instead of subtracting a number, we can add its negative counterpart. For example, the expression -6 - 7 can be rewritten as -6 + (-7).

Why is this important?

Rewriting subtraction expressions as addition expressions is crucial in mathematics because it helps us to simplify complex expressions and make them easier to evaluate. By converting subtraction to addition, we can use the commutative and associative properties of addition to simplify the expression.

Example 1: -6 - 7

Let's start with the first expression: -6 - 7. To rewrite this expression as an addition expression, we need to add the negative counterpart of 7, which is -7. Therefore, the expression -6 - 7 can be rewritten as -6 + (-7).

How to evaluate the expression?

To evaluate the expression -6 + (-7), we need to add the two numbers together. Since both numbers are negative, the result will be a negative number. To add two negative numbers, we need to add their absolute values and then apply the negative sign. The absolute value of -6 is 6, and the absolute value of -7 is 7. Therefore, the sum of the two numbers is 6 + 7 = 13. Since both numbers are negative, the result is -13.

Example 2: 5 - (-8)

The second expression is 5 - (-8). To rewrite this expression as an addition expression, we need to add the negative counterpart of -8, which is 8. Therefore, the expression 5 - (-8) can be rewritten as 5 + 8.

How to evaluate the expression?

To evaluate the expression 5 + 8, we need to add the two numbers together. Since both numbers are positive, the result will be a positive number. The sum of the two numbers is 5 + 8 = 13.

Example 3: -8 - 9

The third expression is -8 - 9. To rewrite this expression as an addition expression, we need to add the negative counterpart of 9, which is -9. Therefore, the expression -8 - 9 can be rewritten as -8 + (-9).

How to evaluate the expression?

To evaluate the expression -8 + (-9), we need to add the two numbers together. Since both numbers are negative, the result will be a negative number. To add two negative numbers, we need to add their absolute values and then apply the negative sign. The absolute value of -8 is 8, and the absolute value of -9 is 9. Therefore, the sum of the two numbers is 8 + 9 = 17. Since both numbers are negative, the result is -17.

Example 4: 7 - (-2)

The fourth expression is 7 - (-2). To rewrite this expression as an addition expression, we need to add the negative counterpart of -2, which is 2. Therefore, the expression 7 - (-2) can be rewritten as 7 + 2.

How to evaluate the expression?

To evaluate the expression 7 + 2, we need to add the two numbers together. Since both numbers are positive, the result will be a positive number. The sum of the two numbers is 7 + 2 = 9.

Example 5: -3 - 4

The fifth expression is -3 - 4. To rewrite this expression as an addition expression, we need to add the negative counterpart of 4, which is -4. Therefore, the expression -3 - 4 can be rewritten as -3 + (-4).

How to evaluate the expression?

To evaluate the expression -3 + (-4), we need to add the two numbers together. Since both numbers are negative, the result will be a negative number. To add two negative numbers, we need to add their absolute values and then apply the negative sign. The absolute value of -3 is 3, and the absolute value of -4 is 4. Therefore, the sum of the two numbers is 3 + 4 = 7. Since both numbers are negative, the result is -7.

Conclusion

In this article, we have learned how to rewrite subtraction expressions as addition expressions and find the sum of each new expression. By converting subtraction to addition, we can use the commutative and associative properties of addition to simplify the expression. We have also seen how to evaluate the resulting expressions by adding the two numbers together. By following these steps, we can simplify complex expressions and make them easier to evaluate.

Key Takeaways

Subtraction is the opposite of addition.
To rewrite a subtraction expression as an addition expression, we need to add the negative counterpart of the number being subtracted.
To evaluate an expression with two negative numbers, we need to add their absolute values and then apply the negative sign.
By converting subtraction to addition, we can use the commutative and associative properties of addition to simplify the expression.

Final Thoughts

Rewriting subtraction expressions as addition expressions is a powerful tool in mathematics that can help us to simplify complex expressions and make them easier to evaluate. By following the steps outlined in this article, we can master this technique and become more confident in our ability to solve mathematical problems.
Directions: Find the Sum of Each New Expression

Rewriting Subtraction Expressions as Addition Expressions

Rewriting Subtraction Expressions as Addition Expressions

Why is this important?

Example 1: -6 - 7

How to evaluate the expression?

Example 2: 5 - (-8)

How to evaluate the expression?

To evaluate the expression 5 + 8, we need to add the two numbers together. Since both numbers are positive, the result will be a positive number. The sum of the two numbers is 5 + 8 = 13.

Example 3: -8 - 9

How to evaluate the expression?

Example 4: 7 - (-2)

How to evaluate the expression?

To evaluate the expression 7 + 2, we need to add the two numbers together. Since both numbers are positive, the result will be a positive number. The sum of the two numbers is 7 + 2 = 9.

Example 5: -3 - 4

How to evaluate the expression?

Conclusion

Key Takeaways

Subtraction is the opposite of addition.
To rewrite a subtraction expression as an addition expression, we need to add the negative counterpart of the number being subtracted.
To evaluate an expression with two negative numbers, we need to add their absolute values and then apply the negative sign.
By converting subtraction to addition, we can use the commutative and associative properties of addition to simplify the expression.

Final Thoughts

Q&A: Directions: Find the Sum of Each New Expression

Q: What is the opposite of addition?

A: The opposite of addition is subtraction.

Q: How do we rewrite a subtraction expression as an addition expression?

A: To rewrite a subtraction expression as an addition expression, we need to add the negative counterpart of the number being subtracted.

Q: What is the negative counterpart of a number?

A: The negative counterpart of a number is the number with the opposite sign.

Q: How do we evaluate an expression with two negative numbers?

A: To evaluate an expression with two negative numbers, we need to add their absolute values and then apply the negative sign.

Q: What is the commutative property of addition?

A: The commutative property of addition states that the order of the numbers being added does not change the result.

Q: What is the associative property of addition?

A: The associative property of addition states that the order in which we add numbers does not change the result.

Q: How can we use the commutative and associative properties of addition to simplify an expression?

A: We can use the commutative and associative properties of addition to simplify an expression by rearranging the numbers and combining like terms.

Q: What is the importance of rewriting subtraction expressions as addition expressions?

A: Rewriting subtraction expressions as addition expressions is important because it helps us to simplify complex expressions and make them easier to evaluate.

Q: How can we apply the concept of rewriting subtraction expressions as addition expressions to real-life problems?

A: We can apply the concept of rewriting subtraction expressions as addition expressions to real-life problems by using it to simplify complex expressions and make them easier to evaluate.

Q: What are some common mistakes to avoid when rewriting subtraction expressions as addition expressions?

A: Some common mistakes to avoid when rewriting subtraction expressions as addition expressions include forgetting to add the negative counterpart of the number being subtracted and not applying the negative sign correctly.

Q: How can we practice rewriting subtraction expressions as addition expressions?

A: We can practice rewriting subtraction expressions as addition expressions by working through examples and exercises, and by using online resources and math software to help us practice.