Draw one line on a minus sign and it turns into a plus.
The minus sign is just one flat line. Add a line going up and down, and suddenly it becomes a plus sign!
💡 Phép trừ cơ bản — Fun Facts
Fun “Did you know?” facts about Phép trừ cơ bản — tap through 10 at a time!
You can check subtraction by adding the answer back.
7 − 3 is 4. To check, add it back: 4 + 3 makes 7 again! Addition and subtraction are helpful partners.
Subtraction is the opposite of addition — it undoes it.
Adding puts things together, and subtracting takes them apart. They are like a pair that work in opposite ways.
If you take a number away from itself, you are left with zero.
Have 4 cookies and eat all 4? Now you have 0. Taking the whole amount away leaves you with nothing.
When you take zero away, the number stays the same.
Taking away nothing changes nothing. So 6 − 0 is still 6. Zero is a very polite number to subtract!
The minus sign (−) tells you to take away.
That little dash means 'subtract'. So 5 − 2 means start with 5 and take 2 away, leaving you with 3.
Subtracting means taking some away to get a smaller number.
If you have 5 balloons and 2 pop, you take 2 away and 3 are left. Taking away always makes the amount smaller.