SOLUTION: solve by addtion method 2x-4y=7 4x+2y=9

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Question 34638: solve by addtion method 2x-4y=7
4x+2y=9
Answer by askmemath(368) About Me  (Show Source):
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2x-4y=7
(4x+2y=9)*2
2x-4y=7
8x+4y=18
Adding
10X = 25
X = 25/10 = 5/2
Substitute this into any of the above equations to get the value of Y
Substituting in the first Equation
2%285%2F2%29+-4y+=+7
5+-4y+=+7
Re-Arranging
5-7 = 4y
-2 = 4y
Dividing by 4 on both sides
y = -2/4
Y = -1/2