Ask a question

How we add numbers with different signs

I need to put in words how do we add numbers worn different signs. I need to explain. I'm really not sure how to do this. 


Dianna, The reason your teacher would have assigned this to you is for an exercise in getting you to Understand what is happening.  Many times a student can learn how to mechanically do something without understanding it.  You can memorize a definition from a dictionary but still not really understand the word.
SO now that you have an idea how to do it - do it again - explain it in a different way in your own words.
The two best ways to really and truly learn something are to explain it in your own words or to teach it to someone else.

2 Answers by Expert Tutors

Tutors, sign in to answer this question.
Nataliya D. | Patient and effective tutor for your most difficult subject.Patient and effective tutor for your mos...
Positive number is always larger.
When you add number with different signs, find the difference and use the sign of a number with the bigger absolute value. I will use Jame's examples

29 +(- 54) = - 25
54 - 29 = 25
|29| < |-54| so the answer will be negative number.

- 17 + 47 = 30
47 - 17 = 30
|47| > |- 17| so the answer is positive.

By real life's words this problem will be:

You earned $29, it's "+" for your pocket, and you spend/borrow $54, which is "-" for your pocket.

If you spend more than you earn, result is negative.
If you earn more than you spend result is positive.
James S. | MS in Mechanical Engineering for Any Level Math and ScienceMS in Mechanical Engineering for Any Lev...
5.0 5.0 (364 lesson ratings) (364)
If two numbers have different signs and you want to add them, all you have to do is subtract them! And don't forget, whichever number is larger will have the same sign as your answer!
4 + (-3) = 1
(-17) + 47 = 30
29 + (-54) = -25