Minus is plus the opposite
Turn every − into + to find the terms.
No plus sign!
The expression 83 − 14 has no + sign. Terms are separated by + signs.
What are its terms?
What this lesson covers
The idea
Subtracting a number is the same as adding its inverse, the number with the opposite sign, so all subtractions are converted to additions to identify the terms and a subtracted number becomes a negative term.
No plus sign!
The expression 83 − 14 has no + sign. Terms are separated by + signs.
What are its terms?
- 83 and 14
- 83 and −14
- It has only one term
Change every − into +
Tap each − to change it into + (negative number). Then cut at every + to find the terms.
Subtracting is adding the inverse
The inverse of a number is the number with the opposite sign. The inverse of 14 is −14. The inverse of −14 is 14. Subtracting 14 is the same as adding −14.
Subtracting a number is the same as adding its inverse (the number with the opposite sign). So every subtraction is turned into an addition to find the terms, and a subtracted number becomes a negative term.
- Expression | As a sum | Terms
- 83 − 14 | 83 + (−14) | 83, −14
- −18 − 3 | −18 + (−3) | −18, −3
- 2 − 10 + 4 × 6 | 2 + (−10) + 4 × 6 | 2, −10, 4 × 6
Notes
Subtracting a number is the same as adding its inverse. All subtractions are turned into additions to find the terms, so a subtracted number becomes a negative term.
Check yourself
What is the inverse of −14?
Which shows 20 − 8 as a sum of terms?
How many terms does 9 − 4 + 7 − 2 have?
Answer: 4
9 − 4 + 7 − 2 = 9 + (−4) + 7 + (−2). The terms are 9, −4, 7 and −2.
- −14. −14 is the number itself, with the same sign.
- 0. The inverse is the number with the opposite sign, not zero.
- 14 — correct. Yes! The inverse has the opposite sign.
- 20 + 8. That adds 8. Subtracting 8 means adding −8.
- (−20) + 8. That is −12, not 12. The 20 keeps its sign, and the 8 turns negative.
- 20 + (−8) — correct. Yes! Subtracting 8 is adding −8.