16)
a) x + y + z = 43 - 11 = 32
b) 5z + 3x + 4y = 59 - 27 = 32
c) x - 2y + 13 = 52 = > x - 2y = 52 - 13 = 39
3x - 6y + 1 = 3× (x - 2y) + 1 = 3 × 39 + 1 = 117 + 1 = 118
17) a + b = 13
1 + 12 =
2 + 11 =
3 + 10 =
4 + 9 =
5 + 8 =
6 + 7 =
a = {1 , 2, 3, 4, 5 , 6, 7, 8, 9, 10, 11, 12}
b = { 12. 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1}
18) a + b = 8 ; a > b
5 + 3 = 8
6 + 2 = 8
7 + 1 = 8
