Раскрыть скобки и выражения -(x+-8) (21--2a) -(13+b)+(-b-13) 2(3-+x) -4(y+5)+(12-y) -(7-x)+4(x-5) -9(y-+y) 7/8*(4-/4+x) -(3/19-y)-1/2(y+2/19) -7/13*(26/27+/9-x) -(1/16-y)-1/2(y+2/19) .

-(х+4)-(2х-8) = -х - 4 - 2х + 8 = -3х +4
(21-а)-(20-2а) = 21 - а - 20 + 2а = 1 + а
-(13+b)+(-b-13) = -13 - b - b - 13 = -26 - 2b
2(3-х)-(8+х) = 6 -2х - 8 - х = -2 - 3х
-4(у+5)+(12-у) = -4у - 20 + 12 - у = -5у -8
-(7-х)+4(х-5) = -7 + х + 4х - 20 = -27 + 5 х
-9(у-4) -(12+у) = -9у + 36 - 12 - у = -10у + 24
7/8*(4-х)-(3/4+х) = 7/2 - 7/8 х - 3/4 - х = 11/4 - 15/8 х = 2 3/4 - 1 7/8 х
-(3/19-у)-1/2(у+2/19) = - 3/19 + у - 1/2 у - 1/19 = -4/19 + 1/2у
-7/13*(26/27+х)-(4/9-х) = -182/351 - 7/13 х - 4/9 + х = -218/351 + 6/13 х
-(1/16-у)-1/2(у+2/19) = - 1/16 + у - 1/2у - 1/19 = - 305/304 + 1/2у