若等腰三角形的两边长分别是3cm和8cm,那么这三角形的周长为( )。 A.14cm B.19cm C.14cm或
\u5728\u7b49\u8170\u4e09\u89d2\u5f62ABC\u4e2d\uff0c\u5b83\u7684\u4e24\u8fb9\u957f\u5206\u522b\u4e3a8cm\u548c3cm\uff0c\u5219\u5b83\u7684\u5468\u957f\u4e3a\uff08\u3000\u3000\uff09 A\uff0e19cm B\uff0e19cm\u621614cm C\uff0e11\u5f53\u8170\u957f\u4e3a8cm\u65f6\uff0c\u4e09\u8fb9\u957f\u4e3a\uff1a8\uff0c8\uff0c3\uff0c\u80fd\u6784\u6210\u4e09\u89d2\u5f62\uff0c\u6545\u5468\u957f\u4e3a\uff1a8+8+3=19cm\uff0e\u5f53\u8170\u957f\u4e3a3cm\u65f6\uff0c\u4e09\u8fb9\u957f\u4e3a\uff1a3\uff0c3\uff0c8\uff0c3+3\uff1c8\uff0c\u4e0d\u80fd\u6784\u6210\u4e09\u89d2\u5f62\uff0e\u6545\u4e09\u89d2\u5f62\u7684\u5468\u957f\u4e3a19cm\uff0e\u6545\u9009A\uff0e
\u8bbe\u4e00\u8170\u957f\u4e3axCM\uff0c\u5e95\u957f\u4e3ayCM
x+x/2=14 \u6216 y+x/2=14
y+x/2=18 \u6216 x+x/2=18
\u7531\u7b2c\u4e00\u7ec4\u65b9\u7a0b\u7ec4\u89e3\u5f97x=28/3 y=40/3
\u7531\u7b2c\u4e8c\u7ec4\u65b9\u7a0b\u7ec4\u89e3\u5f97x=12 y=8
\u5219\u5404\u8fb9\u957f\u4e3a28/3CM\u300128/3CM\u300140/3CM\u621612CM\u300112CM\u30018 CM
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