Circle A has a radius of 2 and a center at (8,3). Circle B has a radius of 3 and a center at (3,5). If circle B is translated by <2,4>, does it overlap circle A? If not, what is the minimum distance between points on both circles?

1 Answer
Jul 26, 2018

no overlap ,4.22

Explanation:

What we have to do here is compare the distance (d)
between the centres 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 the new centre of B
under the given translation

under the translation <2,4>

(3,5)(32,5+4)(1,9)new centre of B

to calculate d use the distance formula

xd=(x2x1)2+(y2y1)2

let (x1,y1)=(8,3) and (x2,y2)=(1,9)

d=(18)2+(93)2=49+36=859.22

sum of radii =2+3=5

since sum of radii<d then no overlap

min. distance =d sum of radii

×××××=9.225=4.22
graph{((x-8)^2+(y-3)^2-4)((x-1)^2+(y-9)^2-9)=0 [-40, 40, -20, 20]}