The fact that we know that both functions are parallels, tell us that the slope of both functions are the same.
So we know that our function has to have the next equation:
Y = 1/2x + b
We know that it passes through the point (4,3) so we can replace the X with the 4, and the Y with 3 in order to be able to isolate B.
3 = 1/2 . 4 + b
3 = 2 + b
3 - 2 = b
1 = b
So the equation of the line is:
Y = 1/2 x + 1