[計量] 請問兩題計量

看板GRE作者 (雷龍出國了~~帳號代管中)時間16年前 (2009/10/26 23:03), 編輯推噓2(201)
留言3則, 2人參與, 最新討論串3/6 (看更多)
1) For the line with equation y=ax+b, ab <> 0( not equal to zero) the x -intercept is twice the y-intercept A: slope of the line B: 1/2 2)Graph of equation y= ax+b , ab<>0 has equal x-and y-intercept. A: slope of graph B: -1 這兩題應該答案都是D 無法比較吧 因為雖然知道intercept的比例,但仍無法判定slop會是正是負 為想問這題是因為碰巧看到了國外論壇的解題 ====================================================================== Soln1> The slope of the given line can be positive or negative. i.e 1/2 or -1/2. ( I hope you know how to calculate slope) [Hence soln should be D.] But if you go by equations i.e by substituting x=0 and y=0 seperately. I got -1/2 so soln should be B Soln2> Similar argument it can be positive or negative i.e 1 or -1 [Hence solution should be D.] But again While solving we get slope as -1 so soln is C ======================================================================== 都不是D........ 怎麼會這樣 冏 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 124.8.144.211

10/26 23:38, , 1F
第二個是一定對的 之前就有人問過了~
10/26 23:38, 1F

10/26 23:41, , 2F
文章是哪一篇?我搜尋"slope"沒看到文
10/26 23:41, 2F

10/26 23:48, , 3F
抱歉我也找不到了 我盡量在回文中解釋囉~
10/26 23:48, 3F
文章代碼(AID): #1AvRexGK (GRE)
文章代碼(AID): #1AvRexGK (GRE)