4*9*12*27=11664=108^2, можно.
108/4=27,
4/9=12/27, 4/12=9/27, 27/12=9/4, 27/9=12/4.
(x-(2xy-3x))-4xy+5x-(7-(2-(4-xy-x-y))-25)=
x-2xy+3x-4xy+5x-(7-(2-4+xy+x+y)-25)=
x-2xy+3x-4xy+5x-(7-2+4-xy-x-y-25)=
x-2xy+3x-4xy+5x-7+2-4+xy+x+y+25=
x-2xy+3x-4xy+5x+xy+x+y+16=
10x-5xy+y+16=
10*2-5*2*5+5+16=
20-50+5+16=
-9
(х-8)(6-у)=6х-ух-48+8у
(3с+7)(4-3с)=12с+9с²+28-21
(5а²+1)(3у-1)=15а²у-5а²+3у-1
(х+3)(х²-х-1)=х³-х²-х+3х²-3х-3
5(х+2)(х+3)=5(х²+3х+2х+6)=5х²+15х+10х+30
(3а+5)(3а-6)+30=9а²-18а+15а-30+30=9а²-3а
8х-(3х+1)(5х+1)=8х-15х²-3х-5х-1=-15х²-1
(у+2)(у+3)-(у²+у)=у²+3у+2у+6-у²-у=4у+6
(с+2)с+(с+3)(с-3)=с²+2с+с²-3с+3с-9=2с²+2с-9
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