The positive integer solution of bivariate linear equation 3x + y = 9 is______ .

The positive integer solution of bivariate linear equation 3x + y = 9 is______ .

When x = 1, 3 × 1 + y = 9, the solution is y = 6; when x = 2, 3 × 2 + y = 9, the solution is y = 3; when x = 3, 3 × 3 + y = 9, the solution is y = 0 (not conforming to the meaning of the problem, rounding off). Therefore, the positive integer solution of the equation is x = 1y = 6, x = 2Y = 3. So the answer is: x = 1y = 6, x = 2Y = 3