王大爷用32米篱笆围成长方猪圈,一边靠墙怎么围面积最大?面积是多少平方米?
\u752812.4\u7c73\u957f\u7684\u7bf1\u7b06\u9760\u4e00\u9762\u5899\u56f4\u6210\u4e00\u4e2a\u5bbd2.4\u7c73\u7684\u957f\u65b9\u5f62\u732a\u5708.\u8fd9\u4e2a\u732a\u5708\u9762\u79ef\u6700\u5927\u662f\u591a\u5c11\u5e73\u65b9\u7c73?\u9760\u5899\u4e3a\u957f\u65f6\uff0c\u957f\u4e3a\uff1a12.4\uff0d2.4.\u00d72\uff1d7.6\u7c73
\u9762\u79ef\uff1a7.6\u00d72.4\uff1d18.24\u5e73\u65b9\u7c73
\u9760\u5899\u4e3a\u5bbd\u65f6\uff0c\u957f\u4e3a\uff1a\uff0812.4\uff0d2.4\uff09\u00f72\uff1d5\u7c73
\u9762\u79ef\uff1a5\u00d72.4\uff1d12\u5e73\u65b9\u7c73
\u6700\u5927\u4e3a18.24\u5e73\u65b9\u7c73
\u89e3\uff1a\u82e5\u9760\u5899\u7684\u4e00\u8fb9\u662f\u732a\u5708\u7684\u5bbd\uff0c
\u5219\u732a\u5708\u7684\u957f\u4e3a(12.4-2.4)/2=5m
\u732a\u5708\u7684\u9762\u79ef=5*2.4=12\u5e73\u65b9\u7c73
\u82e5\u9760\u5899\u7684\u4e00\u8fb9\u662f\u732a\u5708\u7684\u957f\uff0c
\u5219\u732a\u5708\u7684\u957f\u4e3a12.4-2.4*2=7.6m
\u732a\u5708\u7684\u9762\u79ef=7.6*2.4=18.24\u5e73\u65b9\u7c73
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绛旓細杈归暱涓30绫崇殑姝ｆ柟褰
绛旓細鐚湀鏄闀挎柟褰紝S=a*b 鎵浠ョ尓鍦堥潰绉=23*35=805锛堝钩鏂圭背锛
绛旓細鐢遍鍙煡,鐚湀涓虹煩褰,绡辩瑔鍏ㄩ暱=2X锛5+8锛=26
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绛旓細鍥存垚闀4绫炽佸4绫筹紝闈㈢Н鏈澶 鏈澶ч潰绉槸4*4=16骞虫柟绫
绛旓細灏辨槸杩欎釜
