MathYouLike MathYouLike
  • Toggle menubar
  • Toggle fullscreen
  • Toggle Search
  •    Sign up
  • QUESTIONS
  • TAGS
  • USERS
  • BADGES
  • UNANSWERD
  • ASK A QUESTION
  • BLOG
...

Summer Clouds moderators

10/11/2017 at 14:10
Answers
2
Follow

In the figure, the square is inscribed in the smaller circle, which has a radius of 4 in. The radius of the larger circle is 8 in. What is the total area of the shaded regions? Express your answer in terms of π.
undefined




    List of answers
  • ...
    Phan Thanh Tinh Coordinator 10/11/2017 at 18:55

    The diagonal of the square is : 4 x 2 = 8 (in)

    The edge of the square is : \(\dfrac{8}{\sqrt{2}}=4\sqrt{2}\) (in)

    The area of the square is : \(\left(4\sqrt{2}\right)^2=32\) (in2)

    The area of the large circle is : \(8^2\pi=64\pi\) (in2)

    The area of the small circle is ; \(4^2\pi=16\pi\) (in2)

    The answer is : \(64\pi-16\pi+32=48\pi+32\) (in2)

    Selected by MathYouLike
  • ...
    Dao Trong Luan Coordinator 10/11/2017 at 18:27

    We easy see the diagonal of the square is diameter of smaller circle.

    => The diagonal of the square is: 4.2 = 8 [in]

    => The edge of the square is: \(\dfrac{8}{\sqrt{2}}=4\sqrt{2}\) [in]

    => The area of square is: \(\left(4\sqrt{2}\right)^2=32\left(in^2\right)\)

    The area of smaller square is: 42.3,14 = 50,24 [in2]

    The area of bigger square is: 82.3,14 = 200,96 [in2]

    => The total area of the shaded regions is:

    \(\left(200,96-50,24\right)+32=182,72\left(in^2\right)\)

    \(182,72\approx58,16\pi\)

    So the answer is 58,16\(\pi\)


Post your answer

Please help Summer Clouds to solve this problem!



Weekly ranking


© HCEM 10.1.29.225
Crafted with by HCEM