Q1. Solve the simultaneous equations x + y = 4 , 3x + 2y = 6 by algebraic method (substitution) and graphical method.
Solution :
Algebraic method (substitution) :
Graphical method:
Math Question 請幫幫手啦
2006-11-11 4:40 am
回答 (3)
2006-11-11 4:51 am
✔ 最佳答案
x+y=4x=4-y
Sub x=4-y into 3x+2y=6:
3(4-y)+2y=6
12-3y+2y=6
12-y=6
-y=-6
y=6
Sub y=6 into x=4-y:
x=4-6
x=-2
Therefore,y=6,x=-2
參考: myself
2006-11-11 4:55 am
substitution:
x+y=4 -(1)
3x+2y=6 -(2)
From -(1)
x=4-y -(3)
put (3) into (2)
3(4-y)+2y=6
12-3y+2y=6
12-y=6
y=6
Put y=6 into(1)
x+6=4
x=-2
.
. .x=-2, y=6
Graphical method 打唔到wo,要自己做
x+y=4 -(1)
3x+2y=6 -(2)
From -(1)
x=4-y -(3)
put (3) into (2)
3(4-y)+2y=6
12-3y+2y=6
12-y=6
y=6
Put y=6 into(1)
x+6=4
x=-2
.
. .x=-2, y=6
Graphical method 打唔到wo,要自己做
2006-11-11 4:49 am
x = 4 - y
sub(s = 4 - y) into 3x + 2y = 6
3(4 - y)+2y = 6
12-3y + 2y = 6
12-y = 6
y = 6
2006-11-10 20:50:13 補充：
sorry 打錯少少第2行係: sub(x = 4 - y) into 3x 2y = 6
sub(s = 4 - y) into 3x + 2y = 6
3(4 - y)+2y = 6
12-3y + 2y = 6
12-y = 6
y = 6
2006-11-10 20:50:13 補充：
sorry 打錯少少第2行係: sub(x = 4 - y) into 3x 2y = 6
收錄日期: 2021-04-13 13:21:41
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