精英家教網 > 初中數學 > 題目詳情
Given two non-zero real numbers a and b，satisfy |2a-4|+|b+2|+
(a-3)b2
+4=2a，then the value of a+b is（　�。�
A、-1B、0C、1D、2
分析：本題根據非負數、算術平方根的概念和性質，化簡解答．
解答：解：依題意
.
2a-4
  
.
+
.
b+2
  
.
+
(a-3)b2
=2a-4，
∴2a-4≥0，2a-4+
.
b+2
  
.
+
(a-3)b2
=2a-4，
∴
.
b+2
  
.
+
(a-3)b2
=0，
∴b=-2 a=3，
∴a+b=1．
故選C．
點評：本題主要考查了非負數、算術平方根的概念及性質，通過變形化簡解答．正確理解非負數、算術平方根等概念和性質是解答問題的關鍵．
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