if the gradient is -2 that just means we work back the way, the method i use to find the gradient is y^2-y^1/x^2-x^1 so if we sub the variables in that gives us -18-(-8)/3-x so if we add that up we get -10/3-x, so what has to be on the bottom to get -2? in this case it would be -2 so the overall answer would be -10/5 which would give us a slope of -2 when simplified :) hope this helps
