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Find the equation of a circle if the endpoints of a diameter are A (-1, 3) and B (7, -5).
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
The first thing that we need to do is to get the center of a circle by using the midpoint formula of the two points as follows
Hence, the center of a circle is C (3, -1).
Next, get the radius of a circle by using the distance formula of two points as follows
Therefore, the equation of a circle is
