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## Notation of a integer

Division is often shown in algebra and science by placing the dividend over the divisor with a horizontal line, also called a vinculum or fraction bar, between them. For example, a divided by b is written

$\frac ab$

This can be read out loud as "a divided by b", "a by b" or "a over b". A way to express division all on one line is to write the dividend (or numerator), then a slash, then the divisor (or denominator), like this:

$a/b\,$

This is the usual way to specify division in most computer programming languages since it can easily be typed as a simple sequence of ASCII characters. A typographical variation halfway between these two forms uses a solidus (fraction slash) but elevates the dividend, and lowers the divisor:

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Any of these forms can be used to display a fraction. A fraction is a division expression where both dividend and divisor are integers (although typically called the numerator and denominator), and there is no implication that the division must be evaluated further. A second way to show division is to use the obelus (or division sign), common in arithmetic, in this manner:

$a \div b$

This form is infrequent except in elementary arithmetic. ISO 80000-2-9.6 states it should not be used. The obelus is also used alone to represent the division operation itself, as for instance as a label on a key of a calculator.

In some non-English-speaking cultures, "a divided by b" is written a : b. This notation was introduced in 1631 by William Oughtred in his Clavis Mathematicae and later popularized by Gottfried Wilhelm Leibniz. However, in English usage the colon is restricted to expressing the related concept of ratios (then "a is to b").

In elementary mathematics the notation $b)~a$ or $b \overline{)a}$ is used to denote a divided by b, especially when discussing long division. This notation was first introduced by Michael Stifel in Arithmetica integra, published in 1544.

## Positive and negative

North Carolina was 34 degrees below zero. This number can be written as -34°F. Numbers that are less than zero are negative numbers. They are written with a negative sign in front of them. On a number line, negative numbers are to the left of zero and positive numbers are to the right of zero.Integers are the set of positive whole numbers (1, 2, 3, . . .), their opposites, and zero. Opposites are numbers that are the same distance from zero in opposite directions on a number line. For example the numbers 2 and −2 are opposites. The numbers −8 and 8 are also opposites.What is the opposite of each number below?Locating Integers on a Number Line.Since the number is four places to the left of zero, the number is -4 When determining what number is shown on a number line, remember that negative integers are to the left of zero and positive integers are to the right of zero. The integers on a number line.

## Absolute value

The absolute value of a number is its distance from zero on a number line. You write the “absolute value of −6” as |-6| Notice that opposite numbers have the same absolute value. Since absolute value represents distance, the absolute value of a number is always positive: -|n| means the opposite of the absolute value of n.

• -|2|= -2
• -|65|= -65