28х-4+3х=31х-4
28х+3х-31х= -4+4
0х=0
Ответ:0
1) 11m² -11=11(m² -1)=11(m-1)(m+1)
2) 6a³ - 6a=6a(a² -1)=6a(a-1)(a+1)
3) 5x³ - 5xy² =5x(x² - y²)=5x(x-y)(x+y)
4) 8a²b² - 72a²c²=8a²(b² - 9c²)=8a²(b-3c)(b+3c)
5) 2x² +12xy+72y² = 2(x² +6xy+36y²)=2(x+6y)²
6) -8a⁵ + 8a³ - 2a= -2a(4a⁴ -4a²+1)= -2a(2a² - 1)²
(ay-4by)(-12bx+3ax)=y(a-4b)3x(-4b+a)=y(a-4b)3x(a-4b)=y*3x
(1,2c-3d)*10 при c=5 b d=1,1:
(1,2*5-3*1,1)*10
(6-3,3)*10
2,7*10=27