2 -2 4 -4 2 -2 4 -4 6 -6 y = x + y ● +1 ? +2 ? x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + y ● +1 ? +3 ? x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + y ● +1 ? +4 ? x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + +1 ? +2 ? y ● x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + y ● +1 ? -2 ? x 2 -2 4 -4 2 -2 4 -4 6 -6 y = +1 ? y = +0 ? x + y ● x 2 -2 4 -4 2 -2 4 -4 6 -6 (-5, ) ● (-3, ) ● y ● (3, ) y = ● (6, ) ● x 2 -2 4 -4 2 -2 4 -4 6 -6 X = y ● ● ● ● ● ( ,4) ( ,1) ( ,-2) ( ,-3) x 2 -2 4 -4 2 -2 4 -4 6 -6 y ● y = x 2 -2 4 -4 2 -2 4 -4 6 -6 ● y X = x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + y ● +1 ? -4 ? x 2 -2 4 -4 2 -2 4 -4 6 -6 y = x + +1 ? y ● -5 ? x |