Recall that parallel lines have the same slope.
A line parallel to y= (-3/5)x + 8 would have the same equation EXCEPT for a different constant, C, replacing that '8.'
This new line passes thru (-5,-3). In y= (-3/5)x + C, replace x with -5 and replace y with -3. Then:
-3 = (-3/5)(-5) + C. Find C:
-3 = 3 + C. Thus, C = 6
Thus, the equation of the new line is y= -(3/5)x - 6
Check: Let x = -5 and y = -3. Is the above equation true?
-3 = (-3/5)(-5) - 6
-3 = 3 - 6, or -3 = -3.