Geometry

Question Analysis

The main focus is on determining the radius of a circle plotted in the coordinate plane. The radius is the distance from the center of the circle to any point on its circumference.

 

Key Concept Explanation

In the coordinate plane, if the center of the circle is and a point on the circumference is , the radius can be found using the distance formula . In the case of a grid - based circle, we can also count the grid units from the center to the edge of the circle.

 

Step - by - Step Solution

1. Locate the center of the circle:

By observing the graph, the center of the circle is at the point .

2. Find a point on the circumference:

Notice that the circle intersects the y - axis at (for example).

3. Calculate the radius:

Using the distance formula (or simply counting the grid units), with

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