Explanation:
the slope of a line is defined by the factor "a" of x in an equation of the form y = ax + b
to be safe, let's transform
3x - y = 5
3x = y + 5
y = 3x - 5
the slope is 3, and any parallel line must have the same slope.
and for b we use the point coordinates :
-7 = 3×-3 + b
-7 = -9 + b
2 = b
the equation of the parallel line through (-3, -7) is
y = 3x + 2