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下图所示是一个由2个半圆、2个扇形、一个正方形组成的“心”形图案。已知半圆的直径为10,那么“心”形图案的面积是多少?(注:π取3.14)我是这样解的。扇形所在圆的半径和半圆的直径相等,又和正方形的边长相等,即都为10。两个扇形的圆心角和正方形的一个角正好组成一个平角。由正方形的特征可知,它的一个角为90°,则两个扇形的圆心角之和为90°。那么,两个扇形的面积之和就跟半径为10的
The figure below shows a “heart” pattern consisting of 2 semicircles, 2 sectors and a square. Given that the semicircle has a diameter of 10, what is the area of the “heart” pattern? (Note: π takes 3.14) I did this. The radius of the circle where the fan is located is equal to the diameter of the circle, and equal to the length of the side of the square, ie 10. The angle between the two fan-shaped central angles and the square is exactly one square. The characteristics of the square shows that one of its angles is 90 °, then the sum of the central angles of the two sectors is 90 °. Then, the sum of the area of two sectors is the same as the radius of 10