The answer is D.
First solve for y.
You end up with:
y=-1/2x+3/2
Because they want a parallel line, the slope stays the same.
Our equation will look like
y=-1/2x+b
Now plug in the given coordinates
4=-1/2(6) + b
4=-3+b
b=7
Therefore, the equation of the line is
y = -1/2x + 7
