1)Запишите в стандартном виде многочлен 3a*4b^2+6a^2b+6ba*(-2b)-0.2a*30b2)Вычислите

1)3a*4b^2+6a^2b+6ba*(-2b)-0.2a*30b=12ab+6ab-12ab-6ab=
=6ab-6ab=6ab(a-1)

2)7y^2-(3xy-3y^2)+(2xy-10y^2)=7y-3xy+3y+2xy-10y=-xy
при x=1, y=-2
-(1*(-2))=2

3) (c-4)-3(4-c)=(-1(4-c))-3(4-c)=(-1)(4-c)-3(4-c)=(4-c)-3(4-c)=(4-c)(1-3(4-c))=(4-c)(1-12+3c)=(4-c)(3c-11)

4)5x^2+0.5x=0
x(5x+0,5)=0
x=0
5x+0,5=0
5x=-0,5
x=-0,1

1) 3a*4b+6ab+6ba*(-2b)-0.2a*30b=12ab+6ab-12ab-6ab=6ab-6ab

2) 7y-(3xy-3y)+(2xy+10y)=7y-3xy+3y+2xy+10y=20y-xy=y(20y-x)
При х=1, у=-2
-2(20*(-2)-1)=-2(-40-1)=2*41=82

3) (c-4)-3(4-c)=(-1(4-c))-3(4-c)=(-1)(4-c)-3(4-c)=(4-c)-3(4-c)=(4-c)(1-3(4-c))=
=(4-c)(1-12+3c)=(4-c)(3c-11)

4) 5x+0.5x=0
   5x(x+0.1)=0
5x=0       x+0.1=0
x=0         x=-0.1
Ответ: -0,1; 0.