9.
关于x的不等式2x+a≤-3的解集如图所示,则a的取值是( )
| A. | 0 | B. | -1 | C. | -2 | D. | -3 |
8.若m是任意实数,则点M(m2+2,-2)在第( )象限.
| A. | 一 | B. | 二 | C. | 三 | D. | 四 |
7.在△ABC中,∠C=90°,∠A=30°,若CD是高,且CD=1,则a,b,c三边的长分别是( )
| A. | a=$\sqrt{3}$,b=2,c=$\sqrt{7}$ | B. | a=2,b=$\frac{2\sqrt{3}}{3}$,c=$\frac{4\sqrt{3}}{3}$ | C. | a=$\frac{2\sqrt{3}}{3}$,b=2,c=$\frac{4\sqrt{3}}{3}$ | D. | a=2,b=2,c=4 |
6.下列能判定△ABC为等腰三角形的是( )
0 284688 284696 284702 284706 284712 284714 284718 284724 284726 284732 284738 284742 284744 284748 284754 284756 284762 284766 284768 284772 284774 284778 284780 284782 284783 284784 284786 284787 284788 284790 284792 284796 284798 284802 284804 284808 284814 284816 284822 284826 284828 284832 284838 284844 284846 284852 284856 284858 284864 284868 284874 284882 366461
| A. | AB=AC=3,BC=6 | B. | ∠A=40°、∠B=70° | ||
| C. | AB=3、BC=8,周长为16 | D. | ∠A=40°、∠B=50° |