Номер 729
1) a+(b-c) = a+b-c
2) x-(y+2) = x-y-2
3) m-(-n-k) = m+n+k
4) 9-(a+b+c) = 9-a-b-c
5) x-(-3+y-z) = x+3-y+z
6) m+(8+n-k) = m+8+n-k
7) a-(b-c+d) = a-b+c-d
8) x+(y-z+8) = x+y-z+8
9) m-(-2+n+k) = m+2-n-k
Номер 730
1) 2m-2n = 2*(m-n) 2) 3a-6b = 3*(a-2b) 3)6x+10y = 2*(3x+5y)
3x+3y = 3*(x+y) 2c+8d = 2*(c+4d) 15a-12b = 3*(5a-4b)
-4m-4n = -4*(m+n) 5m-15m = 5m*(1-3) 20c-24d = 4*(5c-6d)