下面唔識..點計??
解下列各聯立方程:
1. {y-3=4x
...... 5x+2y=19
2. {7x+10y=-2
......-3x+4y=5
請寫出各題步驟&答案..
多謝先~
(用電腦打好怪..希望C得明..麻煩了..請快)
解聯立方程..急
2008-02-15 5:54 am
回答 (1)
2008-02-15 8:24 am
✔ 最佳答案
1.從1式得: y = 4x + 3
代入2式: 5x + 2 (4x + 3) = 19
5x + 8x + 6 = 19
x = 1
代入1式: y = 4 + 3
y = 7
2.
從1式得: x = (-2 - 10y) / 7
代入2式: -3( (-2 - 10y) / 7) + 4y = 5
6 + 30y + 28y = 35
y = 0.5
代入1式: 7x + 10 x 0.5 = -2
x = -1
參考: 自己
收錄日期: 2021-04-23 20:22:59
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080214000051KK04520