Follow below steps :-
1. Go to account settings.
2. Select `download a copy` option.
3. Choose `expanded archive` from the next page opened and enter your password and click continue.
4. Select `start my archive`.
5. After a few hours you'll get the download link in your email.
5. Download the file `facebook` and unzip it.
6. Open the folder html and then `friend_requests.html`.
7. You can see the list of your friend requests and pending lists.
Now goto their accounts and click`cancel request.
That's all You are done now. Your account is safe.