2x+12=2y 4x=y x=? y=?
回答 (9)
2017-02-20 1:26 am
✔ 最佳答案
2x+12=2y…… 1式4x=y………………2式
2式 代入 1式
則:2x+12=2·4x
2x+12=8x
12=6x
x=2
將x=2代入 2式
則:4·2=y
y=8
所以x=2, y=8
2017-02-26 2:25 pm
２x+12=2y,2x=2y-12代入4x=y
2(2y-12)=y,4y-24=y,4y-y=24,3y=24,y=8
y=8代入4x=y,4x=8,x=2
2(2y-12)=y,4y-24=y,4y-y=24,3y=24,y=8
y=8代入4x=y,4x=8,x=2
2017-02-23 6:06 pm
2x+12=2y:(1)
4x=y:(2)
Sub (2) into (1):
2x+12=2(4x)
2x+12=8x
6x=12
x=2
Sub x=2 into (2):
y=4*2
=8
4x=y:(2)
Sub (2) into (1):
2x+12=2(4x)
2x+12=8x
6x=12
x=2
Sub x=2 into (2):
y=4*2
=8
2017-03-04 11:06 pm
2x-2y=12
4x-y=0
4x-4y=48
-3y=48
y=-16
4x=-16
x=-4
A:X=-4 Y=-16
4x-y=0
4x-4y=48
-3y=48
y=-16
4x=-16
x=-4
A:X=-4 Y=-16
2017-02-19 10:10 pm
2x+12=2(4x); 2x+12 = 8x; 12 = 6x ; x=2
2(2) +12 = 2y; 4+12 =2y y= 16/2 = 8
2(2) +12 = 2y; 4+12 =2y y= 16/2 = 8
2017-02-19 2:57 pm
2x + 12 = 2y --------equation 1
4x = y --------equation 2
Substitute equation 2 into equation 1
2x + 12 = 2y
2x + 12 = 2(4x)
2x + 12 = 8x
12 = 8x - 2x
12 = 6x
x = 12/6 = 2
When x = 2
From equation 2
y = 4x
y = 4 X 2
y = 8
4x = y --------equation 2
Substitute equation 2 into equation 1
2x + 12 = 2y
2x + 12 = 2(4x)
2x + 12 = 8x
12 = 8x - 2x
12 = 6x
x = 12/6 = 2
When x = 2
From equation 2
y = 4x
y = 4 X 2
y = 8
2017-03-18 10:49 pm
這題用代入消去法就可以解出來
2017-02-19 1:51 pm
2x+12=4y
x-2y=-6 i
4x-y=0 ii
x=6/7
y=24/7
x-2y=-6 i
4x-y=0 ii
x=6/7
y=24/7
2017-02-19 12:04 pm
Ovok
收錄日期: 2021-04-18 16:05:05
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