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问题 解答题
4
x
+
5
y
=13
4
x
-
5
y
=3
．
答案

设a=

1
x
，b=
1
y
，

则原方程组可化为

4a+5b=13(1)
4a-5b=3 (2)

解得：

a=2
b=1

∴原方程组的解为

x=
1
2
y=1
．

单项选择题

Water is (41) important of all the things we (42) and drink. Not many people understand this, (43) it’s quite true. The human body (人体) can go (44) food for a long time, but two (45) three days without water can usually (46) people die.
Many people don’ t understand how much water the human body needs to work well and many people do not drink (47) , even (48) hot weather.
Our body is (49) water, about 65% to 75%, ff we do not have enough water, we’ll (50) tired and many will get ill. So you see, how important water is to us all.

[A] make [B] get[C] let
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单项选择题

歌剧《洪湖赤卫队》，描写土地革命战争时期，一只活跃在地方的赤卫队，在党的领导下同派进行斗争，并取得胜利的故事。故事发生地在（）省。

A、江西

B、四川

C、湖北

D、湖南
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