NYC5648
If Radius BC equals 2, What is the area of the shaded region of the circle formed by the rectangle inscribed in the circle?Can somebody please explain a step-by-step solution please.
Thanks!!!
The diagonal of the rectangle is diameter in the circle and therefore its length is 4.
The right triangle formed by a diagonal and two adjacent sides of the rectangle is a 30-60-90 rectangle (because the short leg is half of the hypotenuse).
The other side of the rectangle is therefore \(2\sqrt{3}.\)
The shaded area can be obtained by subtracting from the circular sector defined by two radii (half diagonals) with an angle of \(120^o\) between them the area of the triangle formed by the same two radii and the long side of the rectangle.
The are of the circular sector is \(\pi\cdot2^2\cdot\frac{120}{360}=\frac{4\pi}{3}\) and the area of the triangle is 1/4 of the area of the rectangle, which is \(2\cdot2\sqrt{3}=4\sqrt{3}.\)
In any parallelogram, so also in a rectangle, the two diagonals divide the paralellogram into four triangles with equal areas.
Two radii with the short side of the rectangle form an equilateral triangle, while two radii with the long side of the rectangle form an isosceles triangle with angles 30-30-120.
The requested area is \(\frac{4\pi}{3}-\sqrt{3}.\)
thanks a lot for you detailed explanation. But I still dont get it.
Maybe I am blind but I dont see it.