Circle A has a radius of 5 5 and a center of (2 ,7 )(2,7). Circle B has a radius of 4 4 and a center of (7 ,3 )(7,3). If circle B is translated by <-1 ,2 ><−1,2>, does it overlap circle A? If not, what is the minimum distance between points on both circles?
1 Answer
Explanation:
What we have to do here is
color(blue)"compare"compare the distance (d) between the centres of the circles to thecolor(blue)"sum of the radii"sum of the radii
• " if sum of radii ">d" then circles overlap"∙ if sum of radii >d then circles overlap
• " if sum of radii"< d" then no overlap"∙ if sum of radii<d then no overlap
"before calculating d we require to find the centre of B under"before calculating d we require to find the centre of B under
"under the given translation"under the given translation
"under a translation "<-1,2>under a translation <−1,2>
(7,3)to(7-1,3+2)to(6,5)larrcolor(red)"new centre of B"(7,3)→(7−1,3+2)→(6,5)←new centre of B
"to calculate d use the "color(blue)"distance formula"to calculate d use the distance formula
•color(white)(x)d=sqrt((x_2-x_1)^2+(y_2-y_1)^2)∙xd=√(x2−x1)2+(y2−y1)2
"let "(x_1,y_1)=(2,7)" and "(x_2,y_2)=(6,5)let (x1,y1)=(2,7) and (x2,y2)=(6,5)
d=sqrt((6-2)^2+(5-7)^2)=sqrt(16+4)=sqrt20~~4.47d=√(6−2)2+(5−7)2=√16+4=√20≈4.47
"sum of radii "=5+4=9sum of radii =5+4=9
"since sum of radii">d" then circles overlap"since sum of radii>d then circles overlap
graph{((x-2)^2+(y-7)^2-25)((x-6)^2+(y-5)^2-16)=0 [-20, 20, -10, 10]}