Negative plus Negative


Before we get started on addition of negative numbers. It’s important to understand the meaning of negative numbers first. A negative number has a value less than zero and is denoted with a minus (-) sign before it.  These numbers can be integers, fractions or decimals. They include -4, -6, -15, -0.5 and -4/5. In addition to that, these numbers are placed on the left side of the number line. Moreover, these numbers are always used to represent a debt, loss or deficiency.

Just like positive numbers, you can also add negative numbers when you understand the concept.  This articles explore examples to add negative numbers.

Addition of negative numbers

When you add a negative number to a negative number, you simply add the numbers and use the negative sign (-) in the answer. Here are simple examples:

-20 + -30 = -50

-60 + -80 = -140

-30 + -90 = -120

-50 + -200 = -250

-90 +-80 = -170

Applications of negative numbers

Negative numbers are used in the fields:


·         Refunds to a debit card and credit card.

·         Annual percentage growth in a particular country (GDP).

·         Rate the inflation indicating fall in normal prices.

·         Interest rates can also be negative.

·         It can represent a debt or deficit.


·         Temperature scale like Celsius.

·         Ions with either negative or positive charge.

·         Latitudes on the south of the equator and longitudes on the west of the prime meridian.

·         Electrical circuits.

·         Topographical features of the earth on height above sea level like Death Valley and Dead Sea.

·         Directional antenna arrays can be negative.


·         Goal difference in football or hockey and point’s difference in rugby or golf.

·         Lap times in formula.

·         Athletics events like hurdles, sprint races, long jump, and triple jump.

·         Club points after deduction.

·         Run differential in baseball.        


·         Video games.

·         Playing audio file.

·         Working hours.

·         Television game shows.

·         A politician approval rating.


Negative addition tutorial


Solved negative addition

What is -20 + -80?

What is -25 + -60?

What is -70 + -15?

What is -31 + -41?

What is -90 + -6?

Frequently Asked Questions

1. What are the rules for adding negative numbers?

The sum of two negative number results a negative number.

2. Where did negative numbers come from?

The negative numbers were used by the Chinese in 200 B.C.E. They used black rods to represent negative numbers while red rods to represent positive numbers. In the 4th century, a mathematician named Alexandrian Diophantus said this equation is absurd.

4X +20= 4

The mathematician argued, that the X should be -4.

In India, negative numbers are traced around (A.D 620-630).

Around 1300, a Chinese mathematician named Chu Shi-Ku gave the “rule of the sign.”

Lastly, in the 16th century around 1545, the study of equation solutions began in Italy.