2x - y = 3 4x = 6 + 2y

We want to solve

2x - y = 3

4x = 6 + 2y

The second equation, after diving through by 2, is

2x = 3 + y

or

2x - y = 3

The system of equations is

2x - y = 3 (1)

2x - y = 3 (2)

These two equations are identical, so we actually have only one equation for determining x and y.

That is,

y = 2x - 3

For any real value of x, there will be a corresponding value of y.

Therefore there an infinite number of solutions, and no unique solution exists.

Answer: There is no unique solution.