He finished ____ the book and returned it to the library. A. read B. to read. C. reading D.reads 答案:C(1)计算: (2)已知(x+2)2+|y+1|=0,化简并求值: .
(1)-1;(2).
【解析】试题分析:(1)根据有理数混合运算法则计算即可;
(2)根据非负数的性质,求出x、y的值,把原式化简后代入即可.
试题解析:【解析】
(1)原式===-1;
(2)∵(x+2)2+|y+1|=0,∴x+2=0,y+1=0,解得:x=-2,y=-1.
原式===
当x=-2,y=-1时,原式==.