Find the radius of the circle if the center is at (1, 2) and the point (-3, 4) lies on the circle. 

The radius of the circle is units.

Explanation:

Given information: (1,2) is center of the circle and the point (-3, 4) lies on the circle.

Distance between any point on the circle from the center of the circle is known as radius.

So, radius of the circle is the distance between two points (1,2) and (-3, 4).

Distance formula:

Using distance formula, we get

On further simplification, we get

Therefore the radius of the circle is units.

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the answer is c. hope is