Which of the following shows a circle circumscribed about a triangle?
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Answer: The first option.
Step-by-step explanation:
1. By definition, when a circle circumscribed about a triangle it passes through all the vertices of that triangle (As you know, a triangle has three vertices).
2. As you can see in the figure attached, the only circle that passes through three vertices of the triangle is the the circle of the first optin. Therefore, you can conclude that that circle is circumscribed about the triangle.