Technically, if the system does not allow you to delete a question of your own, you could flag your question for deletion by a moderator, but they will usually decline the flag, as explained here.
Please take the time reading the last paragraph ("If I flag my post with a request to delete it, what will happen?") of that meta page, and make sure you understand the reasons given there why questions with upvoted answers will usually not be eligible for deletion any more.
That leaves you basically with the following options:
Improve the wording of the question up to the point where it could "help others in the future". Since someone else answered your question and got upvotes for it, at least one or two community members saw probably more value in it than yourself, hence this is often possible.
If you have no clue how to do the former, ask a question at the individual meta site about how your specific question might be improved, or whether the community shares your point of view that the question is not valuable for the site and cannot be improved. If you get support from the community for the latter, that should convince a moderator to accept your request for deletion, or to convince some high rep community members to cast a delete vote.
Have the question dissociated from your account. - That does not delete the question, but it hands the problem over to the community, and the low-quality question will not longer make your account "look bad", if that's your concern.
Do nothing. If your question has really such a low quality as you think, sooner or later it will be closed and users with enough rep can delete it after 48 hours, even with upvoted answers.
Let me add I had a short look into the questions you had asked on Stackoverflow in the past. Even the ones with the most negative voting score give me the impression of having a clear value for the community, especially when you read them in combination with the answers they got. So I see definitely no reason why those questions should be deleted.
