据统计资料,甲、乙两种作物的单位面积产量的比是1:2. 现要把一块长200m、宽100m的长方形土地划分为两块小长方形土地,分别种植这两种作物. 怎样划分这块土地,才能使甲、乙两种作物的总产量的比是3:4?分析:如图10.3-1,一种划分方案为:甲、乙两种作物的种植区域分别为长方形 AEFD 和长方形EBCF.
此时设AE=x m, EB=y m, 根据问题中涉及长度、产量的相等关系,列得方程组
![](http://math.21cnjy.com/mml2svg?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo%3E%7B%3C%2Fmo%3E%3Cmtable+columnalign%3D%22left%22%3E%3Cmtr%3E%3Cmtd%3E%3Cmrow%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmtd%3E%3C%2Fmtr%3E%3Cmtr%3E%3Cmtd%3E%3Cmrow%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmtd%3E%3C%2Fmtr%3E%3C%2Fmtable%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
解这个方程组,得
![](http://math.21cnjy.com/mml2svg?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo%3E%7B%3C%2Fmo%3E%3Cmtable+columnalign%3D%22left%22%3E%3Cmtr%3E%3Cmtd%3E%3Cmrow%3E%3Cmn%3Ex%3C%2Fmn%3E%3Cmo%3E%3D%3C%2Fmo%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmtd%3E%3C%2Fmtr%3E%3Cmtr%3E%3Cmtd%3E%3Cmrow%3E%3Cmi%3Ey%3C%2Fmi%3E%3Cmo%3E%3D%3C%2Fmo%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3Cmn%3E_%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmtd%3E%3C%2Fmtr%3E%3C%2Fmtable%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
过长方形土地的长边上离一端{#blank#}1{#/blank#}处,作这条边的垂线,把这块土地分为两块长方形土地. 较大一块土地种植{#blank#}2{#/blank#}种作物,较小一块土地种植{#blank#}3{#/blank#}种作物.
![](http://tikupic.21cnjy.com/2024/12/17/30/2e/302e4bf122f98fb89b9fa2989099be68_232x147.png)