Question

The diameter of a circle whose area is equal to the sum of the areas of the two circles of radii 40cm and 9cm is

Answer 1

Answer:

Diameter of the given circle is

82cm.

Step-by-step explanation:

Given,

Radius of first circle = 40cm

Radius of second circle = 9cm

Area of the circle = sum of areas of two circles

πR² = π x 40² + π(9)²

=> R² = 1600 + 81

=> R² = 1681

=> R = √1681

=> R = 41cm

Therefore,

Diameter of the given circle = 41 x 2 = 82cm.

Answer 2

Answer:

let the radius of circle be r

then,A.T.G.C.

pi x r2= pi(40 ^2 + 9 ^2)

r2=400+81

r2=4081

r=41

d=82

Step-by-step explanation: