不等式－x＞3的解集是（） A．x＞3　 B．x＜3 C．x＞－3 D．x＜

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问题选择题

不等式－x＞3的解集是（）

A．x＞3　

B．x＜3

C．x＞－3

D．x＜－3

答案

答案：D

利用不等式的基本性质，不等式的两边同时乘以或除以同一个负数不等号的方向改变，不等式两边同除以-1，解得x＜－3，

故选D

填空题

阅读短文，用括号中所给词的适当形式填空。

Mrs. White 1 (have) two children. Tommy is seven, and Annie is four. Tommy 2 (go) to school,

but Annie doesn't. When Tommy 3 (be) at home, he often plays with Annie. Usually he's very nice to

his little sister. One day the two children 4 (play)at home. Suddenly Annie begins 5 (cry).Their

mother runs over and asks, "Why are you crying?" "Tommy breaks (打破) my doll," says Annie. "How

does he break it?" "I hit (打) him on the head with it." 6 (say) Annie.

1.________ 2._______ 3.________ 4.________ 5.________ 6.________

选择题

一个圆的周长增加30%，这个圆的面积增加[ ]

A．30%

B．60%

C．69%