已知x、y是一个正数的两个平方根,且3x+2y=5,求x、y的值.
根据题意,得x+y=0,
所以有:x+y=03x+2y=5,
解得:x=5y=-5,
因此这个正数为25.
_____ was it _____ prevented him from attending the meeting? [ ]
A. What; what
B. What; that
C. It; what
D. That; that
急性阑尾炎最具特征的体征是()
A.转移性右下腹痛
B.右下腹局限性明显压痛
C.膈下常有游离气体
D.白细胞计数大部增多
E.恶心呕吐