2(7-a)=14-2a
5x+3+2(7-x)=5x+3+14-2x=3x+17
7-3(2+c)=7-6-3c=1-3c
21y-(3+y)17=21y-51-17y=4y-51
2x+25+3(x-7)=2x+25+3x-21=5x+4
((15-4x)2-9)2-40=(30-8x-9)2-20=(21-8x)2-20=42-16x-20=22-16x
3(25-x-3(1-y))-6=3(25-x-3+3y)-6= 75-3x-9+9y-9=75-3x+9y
(2(5t+2(15-3c)-k)7+3= (2(5t+30-6c-k)7+3=(10y+60-12c-2k)7+3=70k+140-84c-14k+3=56k+143-84c
(2x-(4-y))5-z=(2x-4+y)5-z=10x-20+5y-z=9z-20+5y
3-(2(11-2(5-3c))-5t)=3-(2(11-10+6c)-5t)=3-(2(1+6c)-5t)=3-(2+12c-5t)=3-2-12c+5t=1-12c+5t