Answer
The perpendicular bisectors of the sides of the triangle.
Work Step by Step
You must draw the perpendicular bisectors of the sides of the triangle because they meet at the circumcenter.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.