I presume you mean to find the line that both of these points lie upon...
y=mx+b
m=slope=(y2-y1)/(x2-x1)=(-7--19)/(-2-1)=12/-3=-4
m=-4 so the line is now:
y=-4x+b, now we can use either point to solve for b, (1,-19) gives you:
-19=-4(1)+b
b=-15 so
y=-4x-15