Question

(3xy-5x+7)-[(2xy+x-2)-(xy+3x-3)] para y=1 e x=-3

Answer 1

(3.3.1 - 5.3 + 7) - [(2.3.1 + 3 - 2)] - (3.1 + 3.3 -3)]
(9-15+7) - [(6+3-2) - (3+9-3)]
(16-15) - [(7) - (9)]
1- [7-9]
1 - [ -2 ]
1 +2
3