It is known that {x = 1, y = - 1 and {x = 2, y = 3 are two solutions of the binary linear equation about X, Y. to solve this equation

It is known that {x = 1, y = - 1 and {x = 2, y = 3 are two solutions of the binary linear equation about X, Y. to solve this equation

Any quadratic equation of two variables can be written as: x + by + C = 0
(Note: there is no a because if there is a, it can also be removed.)
The rest is to solve the equations
Take x = 1, y = - 1 and x = 2, y = 3 to find B and C
The solution is: B = - 1 / 4, C = - 5 / 4
So the equation is: X - 1 / 4 * y - 5 / 4 = 0
Well written: 4x-y = 5