6.
图中A点的坐标可以看做哪个方程组的解( )
| A. | $\left\{\begin{array}{l}{y=-x+5}\\{y=\frac{4}{3}x-2}\end{array}\right.$ | B. | $\left\{\begin{array}{l}{y=-x+5}\\{y=\frac{3}{4}x-2}\end{array}\right.$ | ||
| C. | $\left\{\begin{array}{l}{y=-\frac{5}{4}x+5}\\{y=\frac{3}{2}x-2}\end{array}\right.$ | D. | $\left\{\begin{array}{l}{y=-\frac{5}{4}x+5}\\{y=\frac{2}{3}x-2}\end{array}\right.$ |
5.我县市政工程准备修一条长1200m的污水处理管道,原计划每天修xm,在修完400m后,采用新技术,工效比原来提升了25%,那么增加工作效率后的时间表示为( )
| A. | $\frac{1200}{x}$ | B. | $\frac{1200}{x(1+25%)}$ | C. | $\frac{1200-400}{x(1+25%)}$ | D. | $\frac{1200-400}{x}$ |
3.二元一次方程组$\left\{\begin{array}{l}{x-y=4}\\{x+y=2}\end{array}\right.$的解是( )
| A. | $\left\{\begin{array}{l}{x=3}\\{y=-7}\end{array}\right.$ | B. | $\left\{\begin{array}{l}{x=1}\\{y=1}\end{array}\right.$ | C. | $\left\{\begin{array}{l}{x=7}\\{y=3}\end{array}\right.$ | D. | $\left\{\begin{array}{l}{x=3}\\{y=-1}\end{array}\right.$ |
1.下列各组数可以作为一个三角形三条边长的是( )
| A. | 1,2,4 | B. | 4,5,9 | C. | 4,4,8 | D. | 5,8,11 |
19.为鼓励业主珍惜每一滴水,某小区物业表扬了100个节约用水模范户,5月份用水的情况如表:
那么,5月份这100户平均节约用水的吨数为1.13吨.
0 286820 286828 286834 286838 286844 286846 286850 286856 286858 286864 286870 286874 286876 286880 286886 286888 286894 286898 286900 286904 286906 286910 286912 286914 286915 286916 286918 286919 286920 286922 286924 286928 286930 286934 286936 286940 286946 286948 286954 286958 286960 286964 286970 286976 286978 286984 286988 286990 286996 287000 287006 287014 366461
| 每户节水量(单位:吨) | 1 | 1.2 | 1.5 |
| 节水户数 | 65 | 15 | 20 |