SOLUTION: Write the equation for a circle with center (–9, –2) and tangent to x = –1.

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Question 1074036: Write the equation for a circle with center (–9, –2) and tangent to x = –1.
Found 2 solutions by KMST, ikleyn:
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Point (-9,-2) is at 1 unit distance from line x=-1 ,
so the circle will be a circle of radius R=1
centered at point C%28-9%2C-2%29 , which has system%28x%5BC%5D=-9%2Cy%5BC%5D=-2%29 .

The square of the distance between circle center C
and any circle point P%28x%5BP%5D%2Cy%5BP%5D%29 is
%28x-x%5BC%5D%29%5E2%2B%28y-y%5BC%5D%29%5E2=R%5E2 .
That is true for all points in any circle, with any center and any radius.
That is the equation of a circle.
For this circle,
%28x-%28-9%29%29%5E2%2B%28y-%28-2%29%29%5E2=1%5E2 simplifies to
highlight%28%28x%2B9%29%5E2%2B%28y%2B2%29%5E2=1%29 .

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Point (-9,-2) is at 8 unit distance from line x=-1 ,
so the circle will be a circle of radius R=8
centered at point C%28-9%2C-2%29.



The equation of a circle is
%28x-%28-9%29%29%5E2%2B%28y-%28-2%29%29%5E2=8%5E2 simplifies to
highlight%28%28x%2B9%29%5E2%2B%28y%2B2%29%5E2=64%29 .