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Z
Posts:
17
From:
Artic
Registered:
6/22/13


Re: need help for the circle _
Posted:
Jun 22, 2013 9:54 PM


Hey,
Tangent to the yaxis means that it just touches the yaxis. This is the equation of the circle you desire, (x+5)^2+(y+2)^2=25. You get this because you want the length of the segment that goes from the point (5,2) to the yaxis. This will end up being your radius. Notice (5,2) lies on the line y=2, so you wish to use the distance formula or by simply just looking at it geometrically answer this, how many units do you need to add to 5 to get to 0.....5 right? And remember its always radius^2, hence the 25. Message me if anything is confusing.



