SOLUTION: I need your help solving this using the combination method 2-7x=9y 2y-4x=6 I have tried this 7x-9y=-2 4x-2y=6 but I don't know where or what I did wrong?

Question 569897: I need your help solving this using the combination method
2-7x=9y
2y-4x=6
I have tried this
7x-9y=-2
4x-2y=6 but I don't know where or what I did wrong?

Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
I think you means,"solve this using the elimination method"
:
2 - 7x = 9y
2y -4x = 6
:
Put both equations into standard form
-7x - 9y = -2
7x + 9y = 2; multiplied by -1:
and
2y - 4x = 6
-4x + 2y = 6
:
multiply the 1st equation by 4, and the 2nd equation by 7, results
+28x + 36y = 8
-28x + 14y = 42
-----------------addition eliminates x, find y
0x + 50y = 50
y = 50/50
y = 1
:
Use the 1st original equation to find x, 2 - 7x = 9y
replace y with 1
2 - 7x = 9(1)
-7x = 9 - 2
-7x = 7
x =
x = -1
:
The solutions: x=-1, y=1
:
You can check this in the 2nd original equation
:

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