<span>-15a+20b-35c =-5*(3a-4b+7c)
</span>8a^3b^5-28a^4b^2=4a^3b^2(2b^3-7a)
9x^2y-12x^3y^2+3xy=3xy(3x-4x^2y+1)
система: ((x+y)*5)+((x-y)*3)=230
((X+y)*2)+((x-y)*7)=237
Х^2+y^2+2xy-4y-4x+4
б) 2x^2+y^2+4xy+4xz-4x+2zy-2y-2z+z^2+1
5x-xy-5y+y^2=5(x-y)-y(x-y)=(x-y)(5-y)
1) -2a⁶b³/a³b⁵=-2a³/b².
2) 42m³n⁵/35mn⁵=(6/5)*m²=1,2m².