Hey there!
The square root of 7, or √7 is not a rational number.
As you may have noticed, it is unable to be simplified so that the final answer is number that can be written as a fraction. If you were to try to simplify √7, you will get a result of 2.645751... (the number continues in a random sequence of non terminating decimals).
**Note: A number is only rational if it can be written as a fraction where the numerator and denominator is an integer.
Examples of rational numbers:
12.5 -->
0.333333... -->
Hope this helps and have a nice day! :)