Question

Given center C and a point P on a circle, find its equation. C(-2, 7) and P(1, 11)

Answer 1

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Answer:

  (x +2)² +(y -7)² = 25

Step-by-step explanation:

The length of the radius can be found from the distance formula.

  d = √((x2 -x1)² +(y2 -y1)²)

  d = √((1-(-2))² +(11 -7)²) = √(3² +4²) = √25

The standard form equation of a circle with center (h, k) and radius r is ...

  (x -h)² +(y -k)² = r²

Here, we have (h, k) = (-2, 7) and r = √25, so r² = 25. The circle's equation is ...

  (x +2)² +(y -7)² = 25