**Mathematics: add Simplifying square roots article**

[MaheshCodeReader]

Replace this sentence with a brief description of the awesome changes your PR has. 😊

---

✅️ By submitting this PR, I have verified the following

• [ x] Added descriptive name to PR
  • Your PR should NOT be called Update index.md since it does not help the maintainer understand what has been changed.
  • For example, if you create a Variables article inside the Python directory, the pull request title should be Python: add Variables article.
  • Other examples are Git: edit Git Commit article or PHP: create PHP section and add Data Structures article
• [x ] Reviewed necessary formatting guidelines in CONTRIBUTING.md.
• [x ] No plagiarized, duplicate or repetitive content that has been directly copied from another source.

[honmanyau]

@anuragradha Thank you very much for submitting a pull request (PR)! I have resolved a merge conflict and combined parts of your PR with what was already merged. Happy Hacktoberfest! ☀️