Cartesian coordinate system

👨🏻‍🏫 學術台數學

[匿名]

2013-10-03 3:02 am

O, A(10,5) and B(2,10) are the vertices of triangle OAB as shown in the picture.
Given that C divides OB in the ratio of 1: r and D divides OA in the ratio r:1 , where r > 0

a) Express the coordinates of C and D in terms of r

http://upload.lsforum.net/users/public/u15881cooedinateu64.png

題目話 C divides OB in the ratio of 1: r
究竟是 BC : OC = r:1 定 OC:BC = r : 1 ?????

回答 (4)

少年時

2013-10-08 2:12 am

✔ 最佳答案

C divides OB in the ratio of 1 : r means OC : CB = 1 : r
D divides OA in the ratio r : 1 means OD : DA = r : 1
So,
The coordinates of C is (2/(1+r), 10/(1+r)),
and the coordinates of D is (10r/(r+1), 5r/(r+1)).

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[匿名]

2013-10-04 2:38 am

OC: BC = 1:r
use Section Formula to solve this question

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[匿名]

2013-10-03 6:09 am

C divides OB in 1:r

So, OC : CB = 1 : r

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