the slope of the line of the given equation can bé find in this way: -a/b, where a is the number that multiplies x and b is the number that multiplies y
m = -3/-1 = 3
two parallel lines have the same slope, so also the line that we are a searching has m=3
now we can use this formula
y-y1 = m(x-x1) where y1 and x1 indicate the coordinates of the given point