SOLUTION: Write the standard form of the equations of the circle that is tangent to the line x=3 and has center at (-2, -7)

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Question 337746: Write the standard form of the equations of the circle that is tangent to the line x=3 and has center at (-2, -7)
Found 2 solutions by jim_thompson5910, Fombitz:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Hint: The standard form of a circle is %28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2 where (h,k) is the center and "r" is the radius. So all you really need to do is find the distance from the center to the tangent line to find the radius "r".

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The perpendicular distance from the center to the line x=3 is the radius.
R=3-%28-2%29=5
Use the general equation of a circle centered at (h,k) with radius R.
%28x-h%29%5E2%2B%28y-k%29%5E2=R%5E2
x-%28-2%29%29%5E2%2B%28y-%28-7%29%29%5E2=5%5E2
highlight%28%28x%2B2%29%5E2%2B%28y%2B7%29%5E2=25%29
x%5E2%2B4x%2B4%2By%5E2%2B14y%2B49=25
x%5E2%2B4x%2By%5E2%2B14y%2B28=0