Circle A has a center at #(1 ,4 )# and an area of #28 pi#. Circle B has a center at #(7 ,9 )# and an area of #36 pi#. Do the circles overlap? If not, what is the shortest distance between them?
1 Answer
Mar 12, 2016
circles overlap
Explanation:
First step is to calculate the distance between the centres using the
#color(blue)" distance formula "#
# d = sqrt((x_2-x_1)^2 + (y_2-y_1)^2) # where
#(x_1,y_1)" and " (x_2,y_2)" are 2 coordinate points "# let
#(x_1,y_1)=(1,4)" and " (x_2,y_2)=(7,9) #
hence#d = sqrt((7-1)^2 +(9-4)^2 )= sqrt(6^2+5^2)=sqrt61≈ 7.81# Now require to find radii of circles,using A =
#pir^2# circle A :
# pir^2 = 28pi rArr r^2= 28 rArr r = sqrt28# circle B :
#pir^2 = 36pi rArr r^2 = 36 rArrr = sqrt36 = 6 # radius of A + radius of B =
#sqrt28 + 6 ≈ 11.292 # since the sum of the radii > distance between centres , the circles will overlap