real number that is strictly less than zero From Wikipedia, the free encyclopedia
A negative number, also known as a minus number or below number, is an opposite number that is smaller than zero. For example:
The counting numbers (1, 2, 3, and so on) are all positive numbers. The positive numbers, negative numbers, and the number zero, taken together, are called "signed numbers" or integers.
The number zero is neither positive nor negative. Zero is its own opposite; so +0 = −0. That is, zero steps to the right is the same as zero steps to the left.
A negative number is always less than zero.
A negative number is written by putting a minus sign, "−", in front of a positive number. For example, 3 is a positive number, but −3 is a negative number. It is read "negative three" or "minus three"; it means the opposite of 3.
Negative numbers are left of zero on a number line. A number and its opposite are always the same distance from zero. The negative number −3 is just as far to the left of zero as 3 is to the right of zero:
Sometimes, for emphasis, we write the pair of opposite numbers as −3 and +3.
A number and its opposite always add to zero. So the sum of −3 and +3 is 0. We can write this either as −3 + 3 = 0 or as 3 + (− 3) = 0. In addition, a number and its opposite are said to "cancel each other out".
The set of negative real numbers is sometimes written as .[1]
9 + (−1) = 9 − 1 = 8
6 − (−8) = 6 + 8 = 14
(−3) × (−2) = 3 × 2 = 6
(−4) × 5 = −(4 × 5) = −20
When a person got a debt, people sometimes say that they have a negative amount of money. Negative numbers are used in accounting and science.