Answer:

Explanation:
A rational number is any number that can be expressed as a fraction of two integers, where the denominator is not equal to zero.
In this case, -13 and 18 are both integers, and the denominator 18 is not equal to zero.
Therefore,

Note:
Here is a way to check if a number is rational:
- If the number can be expressed as a fraction of two integers, where the denominator is not equal to zero, then the number is rational.
- If the number cannot be expressed as a fraction of two integers, then the number is irrational.