Circle A has a radius of 1 1 and a center at (2 ,4 )(2,4). Circle B has a radius of 3 3 and a center at (6 ,5 )(6,5). If circle B is translated by <-3 ,4 ><3,4>, does it overlap circle A? If not, what is the minimum distance between points on both circles?

1 Answer
Apr 12, 2016

no overlap , d ≈ 1.099

Explanation:

A translation does not change the shape of a figure, only it's position.

Under a translation of ((-3),(4))

centre of B(6 , 5) → (6 -3 ,5 + 4) → (3 , 9)

Now, require to calculate the distance between the centres of A and B using the color(blue)" distance formula "

color(red)(|bar(ul(color(white)(a/a)color(black)( d = sqrt((x_2 - x_1)^2 + (y_2 - y_1)^2))color(white)(a/a)|)))
where (x_1,y_1)" and " (x_2,y_2)" are 2 coordinate points "

let (x_1,y_1)=(2,4)" and " (x_2,y_2)=(3,9)

d= sqrt((3-2)^2 + (9-4)^2) = sqrt(1+25) = sqrt26 ≈ 5.099

now radius of A + radius of B = 1 + 3 = 4

Since sum of radii < distance between centres , no overlap.

and distance (d) between circles = 5.099 - 4 = 1.099