if x+y=6 and 3x-y=4 then x-y is equal to?
回答 (6)
2016-07-20 8:47 am
x + y = 6 ...... [1]
3x - y = 4 ...... [2]
[2] - [1] :
(3x - y) - (x + y) = 4 - 6
2x - 2y = -2
x - y = -1
3x - y = 4 ...... [2]
[2] - [1] :
(3x - y) - (x + y) = 4 - 6
2x - 2y = -2
x - y = -1
2016-07-20 8:41 am
We can solve this set of simultaneous equations by adding both equations together :
[x + y = 6]
(+)[3x - y = 4]
4x = 10
So x = 2.5
y = 6 - x
y = 6 - 2.5
y = 3.5
Thus, x - y = 2.5 - 3.5 = - 1
Hope this helps !!!!!!!!!!!!!!!!!!!
[x + y = 6]
(+)[3x - y = 4]
4x = 10
So x = 2.5
y = 6 - x
y = 6 - 2.5
y = 3.5
Thus, x - y = 2.5 - 3.5 = - 1
Hope this helps !!!!!!!!!!!!!!!!!!!
2016-07-20 8:59 am
x + y = 6
3x - y = 4
x = 5/2, y = 7/2
x - y = -1
3x - y = 4
x = 5/2, y = 7/2
x - y = -1
2016-07-20 8:58 am
yes
2016-07-20 8:57 am
x + y = 6 .. (1)
3x - y = 4 ... (2)
(1) - (2)
-2x + 2y = 2
x - y = -1
3x - y = 4 ... (2)
(1) - (2)
-2x + 2y = 2
x - y = -1
2016-07-20 8:39 am
4x = 10
x = 5/2
y = 7/2
x - y = 1
x = 5/2
y = 7/2
x - y = 1
收錄日期: 2021-04-20 16:33:22
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