急急急(5分)分坐標

2008-04-27 10:59 pm
(1-2k,3)和(3k,3)兩點相距4個單位,求k的值.

回答 (4)

2008-04-27 11:06 pm
✔ 最佳答案
(1-2k,3) (3k,3)
因爲y軸坐標相等,所以相隔的4個單位是x軸(也就是打橫)
由此可得,
3k-(1-2k)=4
3k-1+2k =4
5k-1 =4
5k =4+1
5k =5
k=1

或者:
(1-2k)-3k=4
1-2k-3k=4
1-5k=4
5k=1-4
5k= -3
k= -3/5
參考: 自己
2008-04-27 11:29 pm
(1-2k,3)同(3k,3)相距4個單位
所以
(1-2k,3)-(3k,3)=(1-5k,0)=(4,0)or(-4,0)
1-5k=4
k=-3/5
1-5k=-4
k=1

k=1or -3/5
2008-04-27 11:07 pm
大家都係同一個y坐標3
所以兩點距離係4即係3k-(1-2k)
4=3k-(1-2k)
5=k
2008-04-27 11:04 pm
3k - (1 - 2k) = 4

3k - 1 + 2k = 4

5k - 1 = 4

5k = 5

k = 1


收錄日期: 2021-05-01 19:43:48
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080427000051KK01677

檢視 Wayback Machine 備份