So first put this in slope intercept form, y=mx+b. subtract x from both sides so now you have 3y=-x+3 and to get y by itself divide both sides by 3 so now you have y=(-x/3) +1 or y=-1/3(x)+1 the slope is m and the y-intercept is b so the slope is -1/3 and the y-intercept is 1
