X^2 = 4Y + 1
X^2 = Y^2 + 4Y - 3
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4Y + 1 = Y^2 + 4Y - 3
Y^2 + 4Y - 3 - 4Y - 1 = 0
Y^2 = 4
Y1 = + 2
Y2 = - 2
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X^2 = 4Y + 1 ( X^2 > 0 )
X1 ^2 = 8 + 1 = 9
X1 = + 3
X2 = - 3
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X2 ^2 = - 8 + 1 = - 7 ( < 0 )
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