Question 1107104:  A circle with centre (2,-3) has a tangent of 24x+7y-12=0. Find the equation of the circle
 
I have no idea how to do this question, please send help! 
 Found 2 solutions by  Alan3354, Edwin McCravy: Answer by Alan3354(69443)      (Show Source): 
You can  put this solution on YOUR website! A circle with centre (2,-3) has a tangent of 24x+7y-12=0. Find the equation of the circle 
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Hint: 
The radial from the center to the tangent line is perpendicular to the tangent line. 
 
 Answer by Edwin McCravy(20064)      (Show Source): 
You can  put this solution on YOUR website! A circle with centre (2,-3) has a tangent of 24x+7y-12=0. Find the equation of the circle. 
Here's the graph:
 
You have the center.  You need the radius, which is the green line.
What you need is the distance formula from a point to a line:
The perpendicular distance from the point (x1,y1)to the line
Ax+By+C=0 is
d =  
Your line is 24x+7y-12 = 0
So you plug in A=24, B=7, C=-12 and (x1,y1) = (2,-3)
Substitute that into the formula for d.  That will be the radius r.
Then substitute (h,k) = (2,-3) and that value of r into
 
If you have any difficulty, tell me in the note form below and I'll
get back to you by email.
Edwin 
 
 
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