如下图,正方形BEFG的边长为7M,正方形ABCD的边长为5M,求阴影部分的面积
\u5982\u4e0b\u56fe\uff0c\u6b63\u65b9\u5f62BEFG\u7684\u8fb9\u957f\u4e3a7\u7c73\uff0c\u6b63\u65b9\u5f62ABCD\u7684\u8fb9\u957f\u4e3a5\u7c73\uff0c\u6c42\u9634\u5f71\u90e8\u5206\u7684\u9762\u79ef\u3002Sacb\uff1d1/2x5x5=12.5\u5e73\u65b9\u7c73
Sgfc=1/2x7x2=7\u5e73\u65b9\u7c73
Scfeb=7x7-7=42\u5e73\u65b9\u7c73
Safe=1/2x7x12=42\u5e73\u65b9\u7c73
\u6240\u4ee5\u9634\u5f71\u9762\u79ef
42+12.5-42\uff1d12.5\u5e73\u65b9\u7c73
\u4e0a\u9762\u4e24\u4e2a\u7a7a\u767d\u4e09\u89d2\u5f62\u9762\u79ef\u5206\u522b\u4e3a0.5*5*5=12.5\u548c0.5*7*\uff087-5\uff09=7\uff0c\u4e0b\u9762\u7a7a\u767d\u4e09\u89d2\u5f62\u9762\u79ef\u662f0.5*7*\uff085+7\uff09=42
\u9634\u5f71\u5904\u9762\u79ef\u4e3a5*5+7*7-12.5-7-42=12.5
解答如图。
亲,图在哪里啊?
我知道图,但我不知道怎么做
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绛旓細42+12.5-42锛12.5骞虫柟绫
绛旓細鎼炰釜鍥剧湅鐪嬪搰
绛旓細闃村奖澶勯潰绉负5*5+7*7-12.5-7-42=12.5
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