Circle A has a radius of 3 and a center of (5,4). Circle B has a radius of 1 and a center of (7,2). If circle B is translated by <3,5>, does it overlap circle A? If not, what is the minimum distance between points on both circles?

1 Answer
Feb 16, 2018

no overlap ,4.602

Explanation:

what we have to do here is compare the distance (d)
to the sum of the radii

if sum of radii>d then circles overlap

if sum of radii<d then no overlap

before calculating d we require to find the centre of
B under the given translation

under the translation <3,5>

(7,2)(7+3,25)(10,3)new centre of B

to calculate d use the distance formula

xd=(x2x1)2+(y2y1)2

let (x1,y1)=(5,4) and (x2,y2)=(10,3)

d=(105)2+(34)2=25+498.062

sum of radii =3+1=4

since sum of radii<d then no overlap

min. distance =d sum of radii

×××××=8.0624=4.062
graph{((x-5)^2+(y-4)^2-9)((x-10)^2+(y+3)^2-1)=0 [-20, 20, -10, 10]}