请教初中数学问题,求高手解答,要有详细步骤哦~
\u8bf7\u6559\u521d\u4e2d\u6570\u5b66\u95ee\u9898\uff0c\u6c42\u9ad8\u624b\u89e3\u7b54\uff0c\u8981\u6709\u8be6\u7ec6\u6b65\u9aa4\u54e6~\uff082\uff09\u5f0f\u53ef\u5316\u4e3a\uff1a
(x+y)(x-2y)=0
\u89e3\u5f97\uff1ax+y=0\u6216 x-2y=0
\u6240\u4ee5\u539f\u65b9\u7a0b\u7ec4\u7b49\u4ef7\u4e8e\uff1a
{ x-y=-2 { x-y=-2
{ x+y=0 \u6216\uff1a{ x-2y=0
\u6613\u89e3\u5f97\uff1a
{ x=-1 \u6216\uff1a { x=-4
{ y=1 { y=-2
\u521d\u4e2d\u6570\u5b66\u5408\u96c6\u767e\u5ea6\u7f51\u76d8\u4e0b\u8f7d
\u94fe\u63a5\uff1ahttps://pan.baidu.com/s/1znmI8mJTas01m1m03zCRfQ
?pwd=1234 \u63d0\u53d6\u7801\uff1a1234
\u7b80\u4ecb\uff1a\u521d\u4e2d\u6570\u5b66\u4f18\u8d28\u8d44\u6599\u4e0b\u8f7d\uff0c\u5305\u62ec\uff1a\u8bd5\u9898\u8bd5\u5377\u3001\u8bfe\u4ef6\u3001\u6559\u6750\u3001\u89c6\u9891\u3001\u5404\u5927\u540d\u5e08\u7f51\u6821\u5408\u96c6\u3002
画树状图得:
(2)∴一共有36种可能的结果,且每种结果的出现可能性相同,
点(3,4),(4,3),(2,6),(6,2)在反比例函数y=
点(2,3),(3,2),(1,6),(6,1)在反比例函数y=
∴点P(m,n)在两个反比例函数的图象上的概率都为:4/36=1/9
∴小芳的观点正确.
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绛旓細锛1锛夎绉熺敤鐢茬璐ц溅 x 杈嗭紝鍒欑鐢ㄤ箼绉嶈揣杞 8-x 杈嗐傚彲鍒椾笉绛夊紡缁勶細4x+2(8-x) 鈮 20 锛寈+2(8-x) 鈮 12 锛岃В寰楋細2 鈮 x 鈮 4 锛屽垯鏈 3 绉嶆柟妗堬細鈶 绉熺敤鐢茬璐ц溅 x = 2 杈嗭紝绉熺敤涔欑璐ц溅 8-x = 6 杈嗭紱鈶 绉熺敤鐢茬璐ц溅 x = 3 杈嗭紝绉熺敤涔欑璐ц溅 8-x = 5 杈嗭紱鈶 ...