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Topic: need help for the circle -_-
Replies: 8   Last Post: Jul 9, 2013 9:27 AM

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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 y-axis means that it just touches the y-axis. 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 y-axis. 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.

Date Subject Author
6/22/13 clarice
6/22/13 Z
6/22/13 Z
6/23/13 clarice
6/23/13 Z
6/23/13 clarice
6/23/13 Z
6/23/13 Z
7/9/13 grei