Ответ:

1) 8(6x - 7) - 17x = 48x - 56 - 17x = 31x - 56

2) 9y - 5(17 - y) = 9y - 85 + 5y = 14x - 85

3)0,6(4x - 3) + 2,1(x - 5) = 2,4x - 1,8 + 2,1x - 10,5 = 4,5x – 12,3

4) 2,5(4a - 8b) - (3a - 4b)×1,4 = 10a - 20b - (4,2a - 5,6b) =

= 10a - 20b - 4,2a + 5,6b = 5,8a - 14,4b

5) -(-5,2 - 3,1c) - (2,4c - 6,4) = 5,2 + 3,1c - 2,4c + 6,4 = 11,6 + 0,7c

6) 9/16( 5 1/3x - 2/3y) - 7/20( 2 6/7x - 5 5/7 y) =

3/16×5x - 3/16×2y - 3/5x + 5/4y = 15/16x - 3/8y - 3/5x + 5/4y = 27/80x - 13/8y