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

1 Answer
Dec 6, 2016

"1- no overlap"1- no overlap
"2-minimum distance is "0.122-minimum distance is 0.12

Explanation:

"1-draw circles given"1-draw circles given

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"2-Translate circle B by (1,3)"2-Translate circle B by (1,3)

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"the new position of circle B is shown in figure below"the new position of circle B is shown in figure below

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"now find distance between "O_1" and "O_Tnow find distance between O1 and OT

O_1O_T=sqrt((2-1)^2+(7-3)^2)O1OT=(21)2+(73)2

O_1O_T=sqrt(1^2+4^2)=sqrt(1+16)=sqrt(17)=4.12O1OT=12+42=1+16=17=4.12

"radius "r_1=2radius r1=2

"radius "r_2=1radius r2=1

r_1+r_2=2+1=3r1+r2=2+1=3

O_1O_T>r_1+r_2" ; no overlap"O1OT>r1+r2 ; no overlap

"minimum distance is AB line segment(colored blue)"minimum distance is AB line segment(colored blue)

AB=O_1O_T-r_1+r_2AB=O1OTr1+r2

AB=4.12-3AB=4.123

AB=0.12AB=0.12