SOLUTION: Determine the radius of the circle, given its centre and a point on its circumfrence. Round the radius to the nearest tenth, if necessary. center (1,1) point (-2,1)

Algebra ->  Circles -> SOLUTION: Determine the radius of the circle, given its centre and a point on its circumfrence. Round the radius to the nearest tenth, if necessary. center (1,1) point (-2,1)      Log On


   

Question 87749: Determine the radius of the circle, given its centre and a point on its circumfrence. Round the radius to the nearest tenth, if necessary.
center (1,1) point (-2,1)
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
The radius of this circle is the distance from the centre to the point on the circumfrence. By inspection, this distance is 3 units. Would you also like the equation of the circle??

Equation of a circle: +%28x-h%29%5E2+%2B%28y-k%29%5E2+=+r%5E2+
Equation of your circle: +%28x-1%29%5E2+%2B%28y-1%29%5E2+=+3%5E2+
Equation of your circle: +%28x-1%29%5E2+%2B%28y-1%29%5E2+=+9+ No extra charge!!

R^2 Retired from SCC