Hi Jaosn,
You are going to need points to solve this problem. Generally speaking, you will be given two points (x1,y1) and (x2,y2). Then use slope formula to find the slope (m)
m = (y2 - y1)/(x2 - x1)
Then using your slope (m) and a point (x1,y1) or (x2,y2), find the equation of the line with point slope form
y-y1=m(x-x1)