Subtract 9: Subtraction Facts
| 10 − 9 = 1 (matching addition: 9 + 1 = 10) |
| 11 − 9 = 2 (matching addition: 9 + 2 = 11) |
| 12 − 9 = 3 (matching addition: 9 + 3 = 12) |
| 13 − 9 = 4 (matching addition: 9 + 4 = 13) |
| 14 − 9 = 5 (matching addition: 9 + 5 = 14) |
| 15 − 9 = 6 (matching addition: 9 + 6 = 15) |
| 16 − 9 = 7 (matching addition: 9 + 7 = 16) |
| 17 − 9 = 8 (matching addition: 9 + 8 = 17) |
| 18 − 9 = 9 (matching addition: 9 + 9 = 18) |
| 19 − 9 = 10 (matching addition: 9 + 10 = 19) |
| 20 − 9 = 11 (matching addition: 9 + 11 = 20) |
| 21 − 9 = 12 (matching addition: 9 + 12 = 21) |
Zoorithmetic https://zoorithmetic.com/
Subtract 9 has the best shortcut in subtraction: take away 10 and put 1 back.
The pattern in the answers
Each answer is one more than the ones digit of the starting number: 15 - 9 = 6, 16 - 9 = 7 and 17 - 9 = 8.
Tip for the subtract 9 facts
For 15 - 9, take away 10 to get 5, then put 1 back to get 6.
The 3 hardest facts
- 15 − 9 = 6 (matching addition: 9 + 6 = 15)
- 16 − 9 = 7 (matching addition: 9 + 7 = 16)
- 17 − 9 = 8 (matching addition: 9 + 8 = 17)
These are the facts where the ones digit jumps and children forget to put the 1 back. Say it aloud: take ten, give one back.
Check with addition
Every subtraction fact is an addition fact turned around. Add the answer back to 9 to get the number you started with.
- 1 + 9 = 10, so 10 − 9 = 1
- 2 + 9 = 11, so 11 − 9 = 2
- 3 + 9 = 12, so 12 − 9 = 3
- 4 + 9 = 13, so 13 − 9 = 4
- 5 + 9 = 14, so 14 − 9 = 5
- 6 + 9 = 15, so 15 − 9 = 6
- 7 + 9 = 16, so 16 − 9 = 7
- 8 + 9 = 17, so 17 − 9 = 8
- 9 + 9 = 18, so 18 − 9 = 9
- 10 + 9 = 19, so 19 − 9 = 10
- 11 + 9 = 20, so 20 − 9 = 11
- 12 + 9 = 21, so 21 − 9 = 12
Play the subtract 9 facts game
Untimed by default. A missed fact shows its answer and comes back later in the round.
Printable subtract 9 chart
One US Letter page, clear in black and white.
Quick quiz: subtract 9 facts
10 questions, no timer. At the end you see the score, the facts to practice and a sheet you can print.
Questions parents ask
Does the subtract 9 shortcut work above 19?
Yes. 21 - 9 is 21 - 10 = 11, plus 1 gives 12. This page's largest fact is 21 - 9 = 12.
How is subtract 9 different from subtract 10?
Subtract 10 changes only the tens digit. Subtract 9 does the same and then puts 1 back.