19.不等式组$\left\{\begin{array}{l}-2x<4\\ \frac{1}{2}x-1>0\end{array}\right.$的解集是( )
| A. | x>2 | B. | x>-2 | C. | -2<x<2 | D. | x<-2或 x>2 |
18.不等式1-2x<1 的解集是( )
| A. | x>-1 | B. | x<-1 | C. | x>1 | D. | x>0 |
14.
如图,?ABCD中,AB=3,BC=5,AE平分∠BAD交BC于点E,则CE的长为
( )
( )
| A. | 1 | B. | 2 | C. | 3 | D. | 4 |
13.以下列各组数为边长,能构成直角三角形的是( )
0 284899 284907 284913 284917 284923 284925 284929 284935 284937 284943 284949 284953 284955 284959 284965 284967 284973 284977 284979 284983 284985 284989 284991 284993 284994 284995 284997 284998 284999 285001 285003 285007 285009 285013 285015 285019 285025 285027 285033 285037 285039 285043 285049 285055 285057 285063 285067 285069 285075 285079 285085 285093 366461
| A. | 2,3,4 | B. | 3,4,6 | C. | 5,12,13 | D. | 6,7,11 |