The third one, the slope is -1 you recalculate it using the gradient rule= y^2-y^1/x^2-x^1 , choose any two points and one point is one and the other is 2 foe example : x y (0,3)1 (3,0)2 -3/3 = -1 and the line intercept the y axis at 3 so the y-intercept or the C =3
