There is no substantive difference in the questions as far as I can see. But note a few things:
The old question was closed at some point too. It was then reopened.
Your question had already before your post here three votes to reopen. At five it would be open again.
The treatment is thus not as different as it may look at first glance. This type of question is borderline.
Moreover, the standards of the site emerged and became rather more rigid over time. Finally, the user that asked the old question was/is a regular user of the site and is an established mathematician, while you are very new to the site (at least as concerns active participation) and self-identify as a high-school student. (That this last point plays a role may not be all that fortunate, but it does.)