Adding 9

Key notes:

🔢 What Does Adding 9 Mean?
  • Adding 9 means making a number bigger by 9.
  • Example: 5 + 9 = 14
🌟 Key Points

Adding 9 is the same as adding 10 and then taking away 1.

  • Example: 7 + 9 = (7 + 10) – 1 = 17 – 1 = 16

You can use number lines to add 9 by moving 9 steps forward.

You can also use counters, fingers, or objects to add 9.

📊 Number Line Example

👉 Solve 3 + 9 on a number line:

  • Start at 3.
  • Jump 9 steps forward.
  • You land on 12.
    ✅ So, 3 + 9 = 12.
🧮 Examples
  1. 4 + 9 = 13
  2. 6 + 9 = 15
  3. 8 + 9 = 17
  4. 10 + 9 = 19
🎯 Trick to Remember

Think “add 10, subtract 1”

  • 9 + 5 → (5 + 10) – 1 = 14
📝 Practice
  1. 2 + 9 = ____
  2. 7 + 9 = ____
  3. 11 + 9 = ____
  4. 15 + 9 = ____

Learn with an example

🧭Add. 9 + 8 =

  • You can count on to find 9 + 8.
  • Start at 9 and count on 8 times.
  • You end at 17.
  • 9 + 8 = 17

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  • You can also add using doubles minus one.
  • Remember the doubles fact 9 + 9 = 18.
  • Notice that 9 + 8 is 1 less. That makes 17.
  • 9 + 8 = 17

🧭Add. 9 + 0 =

When you add 0 to a number, the number stays the same.

9 + 0 = 9

🧭Add. 9 + 10 =

  • You can count on to find 9 + 10.
  • It is easier to start with the larger number. So, start at 10. Count on 9 times.
  • You end at 19.
  • 9 + 10 = 19

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  • You can also think about place value to add.
  • 9 + 10 is 1 ten and 9 ones.
tensones
19
  • That makes 19.
  • 9 + 10 = 19

Let’s practice!