Circle A has a center at #(8 ,-4 )# and a radius of #3 #. Circle B has a center at #(4 ,3 )# and a radius of #5 #. Do the circles overlap? If not what is the smallest distance between them?

1 Answer
Feb 15, 2016

The circles do not overlap and are separated by a (minimum) distance of (approximately) #0.06# units

Explanation:

The centers of the circles at #(8,-4)# and #(4,3)# are separated by a distance of
#color(white)("XXX")sqrt((8-4)^2+(-4-3)^2)=sqrt(16+49)=sqrt(65)~~8.06#

Measured along the line segment joining the centers
#color(white)("XXX")#the radius of A uses up #3# units
and
#color(white)("XXX")#the radius of B uses up #5# units

which leaves
#color(white)("XXX")8.06 - (3+5) = 0.06# units along which the circles do not overlap.