## Algebra 1

According to the textbook, a number, $a$, is a square root of another number, $b$, if $a^2=b$. The number $\sqrt {144}$ can be simplied to $12$ because $12^2=144$. A natural number is a number in the set $\{1,2,3,…….\}$. $12$ is a natural number because it lies in this set. Since the set of natural numbers is a part of the set of whole numbers, integers, and rational numbers, $12$ must also be a whole number, an integer, and a rational number.