Adding integers: find the missing value | 7th grade | Khan Academy

TL;DR

Learn how to find missing values on a number line by using addition and subtraction with negative numbers.

Transcript

• [Instructor] We are asked to find the missing value, and they give us a hint. Use the number line to find the missing value. And let's see, they say, 4 plus something is equal to -6. So why don't you pause this video and see if you can work through this before we do it ourselves. All right, so let's just start at 4. So there's a couple of ways to... Read More

Key Insights

• 🫥 Addition and subtraction can be represented on a number line.
• #️⃣ Moving to the left on a number line requires adding a negative number.
• 🫥 Counting the units on a number line can help find missing values.
• ❓ The commutative property can be applied to rearrange equations and determine missing values.
• #️⃣ The number line provides a visual representation and aids in understanding addition and subtraction with negative numbers.
• ↔️ Finding missing values on a number line involves starting from a given number and moving left or right based on the given operation.
• 🫥 Different methods can be used to find missing values on a number line, such as counting units or applying the commutative property.

Questions & Answers

Q: How can we use a number line to find missing values?

Using a number line, we can start at a given number and move left or right based on the addition or subtraction to find the missing value.

Q: What happens when we need to move to the left on a number line?

Moving to the left on a number line means adding a negative number. So, to find the missing value, we need to add a negative number equal to the units we need to move to the left.

Q: Can we use the commutative property to find missing values on a number line?

Yes, the commutative property allows us to rearrange the equation and find the missing value. We can swap the positions of the given number and the missing value to determine the missing value.

Q: Are there multiple ways to find missing values on a number line?

Yes, there are multiple methods. One way is to count the units needed to move on the number line, while another way is to use the commutative property to rearrange the equation and find the missing value.

Summary & Key Takeaways

• The video teaches how to find missing values on a number line by using addition and negative numbers.

• To find the missing value, start at a given number and move left or right on the number line based on the given addition or subtraction.

• Two methods are shown: counting the units to move on the number line to reach the missing value and using the commutative property to rearrange the equation and find the missing value.