(3,7y-6)-(-5,3+(-2,4y+7)-11,92)
(3,7y-6)-(-5,3-2,4y+7-11,92) (3,7y-6-(5,3-3-2,4y+7-11,92) 3,7y-6-5,3-2,4y+7-11,92 3,7-6-(-1,7-2,4y-11,92) 3,7y-6(-10,22-2,4y) 3,7y-6+10,22+2,4y 6,1y-6+10,22 6,1y+4,22