SOLUTION: Find all solutions (x,y): 2x-y=2 y^2-4x=4

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Question 205255: Find all solutions (x,y):
2x-y=2
y^2-4x=4
Answer by alicealc(293) About Me  (Show Source):
You can put this solution on YOUR website!
1st equation:
2x - y = 2
2x = 2 + y
divide it by 2:
x = 1 + y/2

2nd equation:
y%5E2-4x=4
y%5E2-4%281%2By%2F2%29=4
y%5E2-4-2y=4
y%5E2-4-2y-4=0
y%5E2-2y-8=0
factorize it:
(y - 4)(y + 2) = 0
y - 4 = 0 --> y = 4 --> x = 1 + 4/2 = 1 + 2 = 3
y + 2 = 0 --> y = -2 --> x = 1 + (-2)/2 = 1 - 1 = 0

so the solutions are: (3, 4) and (0, -2)