一道初一数学题拜托大家急用
\u4e00\u9053\u521d\u4e00\u6570\u5b66\u9898\uff0c\u6025\u7528\u554a\uff0c\u5728\u7ebf\u7b49\u25b3BEC\u548c\u25b3ABC\u76f8\u6bd4\uff0c\u9ad8\u5ea6\u662f\u4e00\u534a\uff08\u56e0\u4e3aE\u662fAD\u4e2d\u70b9\uff09\uff0c\u6240\u4ee5\u9762\u79ef\u4e5f\u662f\u4e00\u534a\uff0c\u7b49\u4e8e12/2=6\uff0c
\u800c\u25b3BEF\u548c\u25b3BEC\u76f8\u6bd4\uff0c\u5e95\u8fb9\u957f\u662f\u4e00\u534a\uff08F\u662fEC\u4e2d\u70b9\uff09\uff0c\u6240\u4ee5\u9762\u79ef\u4e5f\u662f\u4e00\u534a\u7b49\u4e8e6/2=3\uff1b
\uff081\uff09\u89d21\u3001\u89d22\u3001\u89d23\u4e4b\u95f4\u7684\u7b49\u5f0f\u5173\u7cfb\u4e3a\uff1a\u22201+\u22202=\u22203
\u8bc1\u660e\uff1a\u8fc7P\u70b9\u4f5c\u76f4\u7ebfm//L1\u5c06\u22203\u5206\u6210\u2220\u03b1\u548c\u2220\u03b2\uff0c\u5219m\u4e5f\u5e73\u884c\u4e8eL2
\u56e0\u4e3am//L1\uff0c\u6839\u636e\u5b9a\u7406\u2018\u4e24\u76f4\u7ebf\u5e73\u884c\u5176\u5185\u9519\u89d2\u76f8\u7b49\u2019
\u5f97\uff1a\u22201=\u2220\u03b1\uff0c
\u540c\u7406\uff1a\u22202=\u2220\u03b2
\uff082\uff09\u2220BAC\u7684\u5ea6\u6570\u4e3a85\u00b0
1.\u2220BAC\u7684\u5ea6\u6570\u4e3a85\u00b0
\u8bc1\u660e\uff1a\u636e\uff081\uff09\u53ef\u77e5\u2220DBA+\u2220ECA=\u2220BAC
\u5df2\u77e5\u2220DBA=40\u00b0\uff1b\u2220ECA=45\u00b0
\u2234\u2220BAC=\u2220DBA+\u2220ECA=40\u00b0+45\u00b0=85\u00b0
2. \u89d21+\u89d22\u7684\u5ea6\u6570\u4e3a180\u00b0
\u8bc1\u660e\uff1a\u636e\u5b9a\u7406\u2018\u4e24\u76f4\u7ebf\u5e73\u884c\u5176\u540c\u65c1\u5185\u89d2\u4e92\u8865\u2019\uff1b\u22201\u3001\u22202\u4e3a\u5e73\u884c\u76f4\u7ebf\u95f4\u7684\u540c\u65c1\u5185\u89d2\u53ef\u77e5\uff1a
\u22201+\u22202 = 180\u00b0
\u8bc1\u6bd5
[11-X]*10+X=10X+11-X+63
X=2
答：原来的两位数是29
92
是92
题目有问题
设十位为 x 个位为 y
原数为 10 * x + y
对调后 10 * y + x
(10 * y + x) - (10 * x + y)
9 * (y - x) = 63
y - x = 7 & x + y = 11
x + x + 7 = 11
x = 2 ; y = 9
该十位数为 29
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