5.
已知实数a、b在数轴上的对应位置如图所示,化简|a|-|b|+|a-b|-|b-a|结果为( )
| A. | a+b | B. | 3a-3b | C. | a-b | D. | a-3b |
20.
如图是某住宅区的配电房示意图(图中长度单位:m),它是一个轴对称图形,求配电房的高AE(结果精确到0.1m).
(参考数据:sin35°=0.57,cos35°=0.82,tan35°=0.70)
(参考数据:sin35°=0.57,cos35°=0.82,tan35°=0.70)
17.
如图,⊙O的半径是1,AB是⊙O的切线,A是切点,若半径OC∥AB,则阴影部分的面积为( )
| A. | $\frac{π}{4}$ | B. | $\frac{π}{3}$ | C. | $\frac{π}{2}$ | D. | $\frac{3π}{4}$ |
16.
如图,在△ABC中,∠B=85°,∠ACB=45°,若CD∥AB,则∠ACD的度数为( )
0 297643 297651 297657 297661 297667 297669 297673 297679 297681 297687 297693 297697 297699 297703 297709 297711 297717 297721 297723 297727 297729 297733 297735 297737 297738 297739 297741 297742 297743 297745 297747 297751 297753 297757 297759 297763 297769 297771 297777 297781 297783 297787 297793 297799 297801 297807 297811 297813 297819 297823 297829 297837 366461
| A. | 40° | B. | 45° | C. | 50° | D. | 60° |