Answer:
Sum of the areas of the three circles is 91.06 units².
Step-by-step explanation:
Given:
Let the radius of the circle with center D = x
Let the radius of the circle with center E = y
Let the radius of the circle with center F = z
To Find:
Sum of the areas of the three circles = ?
Solution:
So we have these equations
![DE =x + y = 5............( 1 )\\EF = x + z = 6..........( 2 )\\DF =y + z = 7...........( 3 )](https://tex.z-dn.net/?f=DE%20%3Dx%20%2B%20y%20%3D%205............%28%201%20%29%5C%5CEF%20%3D%20x%20%2B%20z%20%3D%206..........%28%202%20%29%5C%5CDF%20%3Dy%20%2B%20z%20%3D%207...........%28%203%20%29)
Subtract the second equation from the first and we have that
![y- z=-1](https://tex.z-dn.net/?f=y-%20z%3D-1)
Add this to equation to the third equation and we have that
![\therefore 2y= 6\\\\\therefore y= 3\\\\\therefore x = 2\\\\\therefore z = 4](https://tex.z-dn.net/?f=%5Ctherefore%202y%3D%206%5C%5C%5C%5C%5Ctherefore%20y%3D%203%5C%5C%5C%5C%5Ctherefore%20x%20%3D%202%5C%5C%5C%5C%5Ctherefore%20z%20%3D%204)
Now we have Area of Circle
![\textrm{Area of Circle}=\pi (Radius)^{2}](https://tex.z-dn.net/?f=%5Ctextrm%7BArea%20of%20Circle%7D%3D%5Cpi%20%28Radius%29%5E%7B2%7D)
Substituting Radius we get
![\textrm{Area of Circle with center D}=3.14\times 2^{2}=12.56\ units^{2}](https://tex.z-dn.net/?f=%5Ctextrm%7BArea%20of%20Circle%20with%20center%20D%7D%3D3.14%5Ctimes%202%5E%7B2%7D%3D12.56%5C%20units%5E%7B2%7D)
![\textrm{Area of Circle with center E}=3.14\times 3^{2}=28.26\ units^{2}](https://tex.z-dn.net/?f=%5Ctextrm%7BArea%20of%20Circle%20with%20center%20E%7D%3D3.14%5Ctimes%203%5E%7B2%7D%3D28.26%5C%20units%5E%7B2%7D)
![\textrm{Area of Circle with center F}=3.14\times 4^{2}=50.24\ units^{2}](https://tex.z-dn.net/?f=%5Ctextrm%7BArea%20of%20Circle%20with%20center%20F%7D%3D3.14%5Ctimes%204%5E%7B2%7D%3D50.24%5C%20units%5E%7B2%7D)
∴ ![\textrm{Sum of the areas of the three circles}=12.56+28.26+50.24=91.06\ units^{2}](https://tex.z-dn.net/?f=%5Ctextrm%7BSum%20of%20the%20areas%20of%20the%20three%20circles%7D%3D12.56%2B28.26%2B50.24%3D91.06%5C%20units%5E%7B2%7D)