题目内容
Given two non-zero real numbers a and b，satisfy |2a-4|+|b+2|+
+4=2a，then the value of a+b is（ ）
| (a-3)b2 |
| A、-1 | B、0 | C、1 | D、2 |
分析：本题根据非负数、算术平方根的概念和性质，化简解答．
解答：解：依题意
+
+
=2a-4，
∴2a-4≥0，2a-4+
+
=2a-4，
∴
+
=0，
∴b=-2 a=3，
∴a+b=1．
故选C．
|
|
| (a-3)b2 |
∴2a-4≥0，2a-4+
|
| (a-3)b2 |
∴
|
| (a-3)b2 |
∴b=-2 a=3，
∴a+b=1．
故选C．
点评：本题主要考查了非负数、算术平方根的概念及性质，通过变形化简解答．正确理解非负数、算术平方根等概念和性质是解答问题的关键．
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