\u521d\u4e2d\u6570\u5b66\uff0c\u8dea\u6c42\u5927\u795e\u5e2e\u52a9

\uff081\uff09\u89e3\u6790\u5f0f\u4e3a W=900-35x \uff085\u2264x\u22649\uff09 \u7531\u89e3\u6790\u5f0f \u53ef\u77e5 x\u8d8a\u5927W\u8d8a\u5c0f\u3002
\u53c8\u2235\uff08\u56e0\u4e3a\uff095\u2264x\u22649 \u2234\uff08\u6240\u4ee5\uff09\u5f53x=9\u65f6\uff0cW\u6709\u6700\u5c0f\u503c
Wmin=585\uff08\u5143\uff09 (\u201cmin\u201d\u662f\u6700\u5c0f\u503c\u7b26\u53f7 )
\uff082\uff09W=900-\uff0825x+10y\uff09 \u7531\u89e3\u6790\u5f0f\u53ef\u77e5 \uff0825x+10y\uff09\u8d8a\u5927 \uff0cW\u8d8a\u5c0f
\u5373\uff0cx\u8d8a\u5927 W\u8d8a\u5c0f \u6240\u4ee5x=10 y=8 \u662f\u6700\u4f73\u65b9\u6848
Wmin=450(\u5143) (\u201cmin\u201d\u662f\u6700\u5c0f\u503c\u7b26\u53f7 )
\u7eaf\u624b\u6253\uff0c\u4eb2\uff0c\u8bb0\u5f97\u7ed9\u91c7\u7eb3\u554a\uff01\uff01\uff01

\u89e3\uff1a\uff081)4
(2)4/1*(3-1)=8
\u5373BC\u95f4\u7684\u8ddd\u79bb\u4e3a8km.
(3)\u8bbe\u9759\u6c34\u901f\u5ea6\u4e3axkm/h\uff0c\u6c34\u6d41\u901f\u5ea6\u4e3aykm/h
2x+2y=8
3x-3y=8
\u89e3\u5f97\uff1a
x=10/3
y=2/3