4 (a+2) 8 (-7x) 12 (x+y) (c-9) * 11 (8+y) * 16 15 (4a-3) 7 (6a+8b) 10 (2m-3n+4r) (24x+17y-36z) * 4

4 (a+2) = 4 а+8

8 (-7x) = - 56 х

12 (x+y) = 12 х+12 у

(c-9) * 11=11 с-99

(8+y) * 16=128+16 у

15 (4a-3) = 60 а-45

7 (6a+8b) = 42 а+56 b

10 (2m-3n+4r) = 20m-30n+40r

(24x+17y-36z) * 4=96x+68y-144z