【Haichuan Teahouse】Brain-teasing Series: The questions are well-structured, but there are few conditions provided
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This post was last edited by Desert Fish on 2021-10-26 at 14:01. In square ABCD, the area of the square is 6 square decimeters. E is the midpoint of BC. What is the area of the shaded region in the figure?
This post was last edited by we11we11 on 2021-10-25 at 22:18. I’m not sure if it’s correct; I’m a bit confused
S1+S2=1.5 S1+S4=1.5 S3_S4=3.0 S3+S2=3.0
And S1+S2+S3+S4=4.5
s3-s4=3.0? ? ? ? Isn’t it addition?
This post was last edited by Wang Genrong on 2021-10-26 at 15:01. Triangles BEF and ADF are similar; the ratio of corresponding sides is 1 to 2, so the ratio of their heights is also 1 to 2； The vertical height from side BE to point F = AB/3 ； With equal base lengths and a height of 1/3, the area is also 1/3; thus, S1 = 1.5/3 = 0.5 ； S2=1.5-0.5=1 ； S4=S2=1 ； Shadow area=1+1=2
The method of solving the equation doesn’t work; one can only use the base of the triangle multiplied by its height, and the result is 2