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 Bivariate Quadratic Puzzle (Posted on 2015-06-14)
Find all pairs (x, y) of integers that satisfy this equation:

1 + x2y = x2 + 2xy + 2x + y

 No Solution Yet Submitted by K Sengupta Rating: 3.0000 (1 votes)

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 computer exploration gives probable solution Comment 2 of 2 |
`x     y-1    -10     11    -12    -73     7`

are found by checking all x from negative one million to positive one million and solving for y in the resulting linear equation in y.

DefDbl A-Z
Dim crlf\$

Form1.Visible = True

Text1.Text = ""
crlf = Chr\$(13) + Chr\$(10)

For x = -1000000 To 1000000
y = (x * x + 2 * x - 1) / (x * x - 2 * x - 1)
yr = Int(y + 0.5)
If Abs((y - yr) / y) < 0.0000001 Then
Text1.Text = Text1.Text & x & "    " & Str(y) & crlf
End If
Next

Text1.Text = Text1.Text & crlf & " done"

End Sub

 Posted by Charlie on 2015-06-14 11:28:53

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