Two circles have the following equations: #(x -1 )^2+(y -4 )^2= 9 # and #(x +6 )^2+(y -9 )^2= 49 #. Does one circle contain the other? If not, what is the greatest possible distance between a point on one circle and another point on the other?

1 Answer
Oct 31, 2016

The circles partially overlap but the larger does not contain the smaller.

The farthest possible distance will be the sum of the two radii plus the distance between the centers: #10 + sqrt(74)#

Explanation:

The radius of the first circle is 3.

The radius of the second circle is 7

The distance between the centers:

#d = sqrt((-6 - 1)^2 + (9 - 4)^2)#

#d = sqrt(74) ~~ 8.6#

The circles partially overlap but the larger does not contain the smaller.

The farthest possible distance will be the sum of the two radii plus the distance between the centers: #10 + sqrt(74)#