问题:
(1)计算: (-1)2007-|-
2
|+(π-2007)0+
8
(2)解方程组:
x-y=2
2x+y=7
.
(1)计算: (-1)2007-|-
|+(π-2007)0+
(2)解方程组:
.
2 |
8 |
(2)解方程组:
|
参考答案: