下列各式成立的是{"A":"-23=-6","B":"12+13=25","C":"3a+2a=5a2","D":"a2=\uff08-a\uff092"}_刷题宝

题干

下列各式成立的是（）

A：-2³=-6

B： $\frac{1}{2}$ + $\frac{1}{3}$ = $\frac{2}{5}$

C：3a+2a=5a²

D：a²=（-a）²

上一题下一题 0.0难度选择题更新时间:2016-10-17 04:20:23

答案(点此获取答案解析）

D

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( A )

Report Card
Name: James Smith		Time: January 24^th, 2015
Subjects	Grades	Comments(评语)
English	B＋	Your reading and writing are good. But you have a strong accent(口音), so you are not good at speaking. And you do not put much effort into this subject. If you work hard, you can get a better grade in this subject.
Physics	A＋	You are good at this subject. You are hardworking. I am glad that you do best in this subject.
Math	C	You like this subject. But you are not good at this subject because you are a little lazy. It is disappointing.You can do better if you try your best.
Music	B	It is a happy thing to hear you play the piano. You are crazy about music. Although you like this subject best, your accent has a bad influence on your singing.

阅读以上成绩单，根据表格内容完成以下问题

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