Ответ:

Объяснение:

1.

30a²+11ab=a(30a+11b)

17m⁵-5m²=m²(17m³-5)

12x²y⁴-18x³y³+6x²y=6x²y(2y³-3xy²+1)

2.

4c(a-c)+7c(a-c)=(a-c)(4c+7c)=11c(a-c)

xz+yz+5x+5y=z(x+y)+5(x+y)=(x+y)(z+5)

3.

5a²-45b⁴=5(a²-9b⁴)=5(a-3b²)(a+3b²)

-4m²+24mn-36n²=-((2m)²-2·2·6mn+(6n)²)=-(2m-6n)²=(2m-6n)(6n-2m)

x³-125y¹²=(x-5y⁴)(x²+5xy⁴+25y⁸)

4.

x³+5x²-25x-125=0

x²(x+5)-25(x+5)=0

(x²-25)(x+5)=0

(x-5)(x+5)(x+5)=0

x-5=0; x₁=5

x+5=0; x₂=-5

5.

(1,6·6,4²-1,6·3,6²)/(0,4·2,4²-0,4³)=(1,6(6,4-3,6)(6,4+3,6))/(0,4(2,4-0,4)(2,4+0,4))=(1,6·2,8·10)/(0,4·2·2,8)=4·5=20