Okay, here we have this:
Slope m=5/3
Pass through the point (-6,-12) and let (x,y) be other point of the line.
m=(x2 - x1)/(y2 - y1)
Replacing we obtain:
(-6 - x)/(-12 - y) = 5/3
Working we obtain:
3 (- 6 - x) = 5 (- 12 - y)
-18 - 3x = -60-5y
-18 - 3x +60+5y = 0
3x - 5y - 42 = 0 (Multiplying by -1 on both sides)
3x - 5y = 42 This is the equation of the line
Clearing y:
y=(42-3x)/-5