2x + 4y = 38
2(x + 2y) = 2(19)
x + 2y = 19
2y = -x + 19
y = (-1/2)x + (19/2)
Thus, you just need to substitute in any value of x, find the resulting value of y, and you will have a set of solution.
For example, let me choose x = 1.
When x = 1, we have:
y = (-1/2)(1) + (19/2)
y = -1/2 + 19/2
y = 18/2
y = 9
Thus, x = 1 and y = 9 is a set of solution.