13.在平面直角坐标系中,点A,B的坐标分别为(2m-2,3),(m,3),且点A在点B的左侧,若线段AB与直线y=-2x+1相交,则m的取值范围是( )
| A. | -1≤m≤$\frac{1}{2}$ | B. | -1≤m≤1 | C. | -$\frac{1}{2}$≤m≤1 | D. | 0≤m≤1 |
12.
如图所示,矩形ABCD中,AB=3,BC=5,点E在AD上,且BE平分∠AEC,则△ABE的面积为( )
| A. | 2.4 | B. | 2 | C. | 1.8 | D. | 1.5 |
11.
将一把直尺与一块三角板如图放置,若∠1=46°,则∠2的度数为( )
| A. | 136° | B. | 138° | C. | 140° | D. | 142° |
10.下列计算正确的是( )
| A. | x+x2=x3 | B. | 2x-3x=-x | C. | (x2)3=x5 | D. | x6÷x3=x2 |
9.使式子$\frac{\sqrt{x+1}}{x-1}$有意义的x的取值范围是( )
| A. | x>1 | B. | x≠1 | C. | x≥-1且x≠1 | D. | x>-1且x≠1 |
7.随着行政区划调整,2017年我区计划新建续建主次干道项目25个,全年计划完成交通投资19.79亿元,其中19.79亿元用科学记数法可表示为( )
| A. | 1.979×107元 | B. | 1.979×108元 | C. | 1.979×109元 | D. | 1.979×1010元 |
6.-$\sqrt{3}$的相反数为( )
0 294382 294390 294396 294400 294406 294408 294412 294418 294420 294426 294432 294436 294438 294442 294448 294450 294456 294460 294462 294466 294468 294472 294474 294476 294477 294478 294480 294481 294482 294484 294486 294490 294492 294496 294498 294502 294508 294510 294516 294520 294522 294526 294532 294538 294540 294546 294550 294552 294558 294562 294568 294576 366461
| A. | $\sqrt{3}$ | B. | -$\frac{\sqrt{3}}{3}$ | C. | 3 | D. | -3 |