Is -5 a irrational number?

Aug 11, 2016

No, $- 5$ is an integer.

Explanation:

There are various number types (natural, whole, integer, rational, real and irrational).

Natural numbers are "counting numbers" like $1 , 2 , 3 , 4$.

Whole/counting are like natural numbers, except that they start from $0$.

Integers are all the whole numbers - positive, negative numbers and 0, but not fractions or decimals.

Rational numbers can be written as $\frac{a}{b} , b \ne 0$
$- 5 \text{ can be written as " (-10)/2, "so it is rational}$
Rational numbers include all the integers, all the vulgar fractions, all the terminating decimals (ones that end, like $0.85$, and all the recurring decimals, unlike $\pi$).

Irrational numbers are infinite decimals which do not recur like $\pi$, $\sqrt{2}$ or $\sqrt{20}$

Non-real/Imaginary numbers do not exist on the numberline,
Numbers like $\sqrt{- 50} , \sqrt{- 16} , 4 i$.

$- 5$ in an integer and is not irrational.