帮我做一条英文的数学题IN the xy-plane,line m is the reflection of line l across the x-asix.If The intersection of lines l and m is the point(r,s),which of the following must be true?A r=0B s=0c r=sD r=-sE rs=-1我知道答案是b,但是不

帮我做一条英文的数学题IN the xy-plane,line m is the reflection of line l across the x-asix.If The intersection of lines l and m is the point(r,s),which of the following must be true?A r=0B s=0c r=sD r=-sE rs=-1我知道答案是b,但是不 帮我做一下下面的数学题 求人帮我做数学题 谁能用英文帮我点评下泰戈尔的诗：The Furthest Distance in the world 请帮我的孩子做道数学题, 一些数学题会的帮我做下. 帮我做这个数学题,高中有关椭圆的 一些数学题会的帮我做下. 谁帮我做一条初一的奥数题：整数x,y满足方程2xy+x+y=83,则x+y=___或___? 谁帮我解一道英文的数学题the ratio of Stan`s age to Fred`s age is 7:12.in 3 year time,their total age will be 101.what is Fred age 17 years from now 做文明市民 创文明城市 帮我翻译成英文 注意这是一条标语 做过英文的数学题的人来帮我!There were 3100 men and women in a convention hall.If 25% of the men left the hall and 400 women came in,there would be an equal number of men and women in the hall.How many women were there in the convention h 帮我孩子做2道数学题, 帮我做个数学题第四题. 帮我做数学题给好评 谁可以帮我做道数学题. 做了几个数学题,帮我看看. 谁帮我做下数学题呀