SOLUTION: Write the equation for a circle that has a center (-2, 4) and radius of 3cm.

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Question 1117203: Write the equation for a circle that has a center (-2, 4) and radius of 3cm.
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Write the equation for a circle that has a center (-2, 4) and radius of 3cm.
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A circle of radius r, center at (h,k):
%28x-h%29%5E2+%2B+%28y-k%29%5E2%29+=+r%5E2
---
the units are not relevant.

Answer by ikleyn(52803) About Me  (Show Source):
You can put this solution on YOUR website!
.
Write the equation for a circle that has a center (-2, 4) and radius of 3 cm.
~~~~~~~~~~~~~~

A circle of radius  r, center at (h,k):


    %28x-h%29%5E2+%2B+%28y-k%29%5E2 = r%5E2              <<<---=== It is the most general equation of a circle in a coordinate plane.


In your case it is 


    %28x-%28-2%29%29%5E2 + %28y-4%29%5E2 = 3%5E2,   or,  simplified as much as possible,


    %28x%2B2%29%5E2 + %28y-4%29%5E2 = 9.

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If you want to learn more on the subject, read the lesson
    - Standard equation of a circle
in this site.