因式分解的题目 中间的什么1⼀4之类的代表四分之一 求求帮帮忙吧 我学的不扎实，要答案就行，我对对答案

-1/4xy³+0.01xy==-xy(y²/4-0.01)=-xy(y/2+0.1)(y/2-0.1)
y²-8y+16=(y-4)²
-4-4xy-x²y²=-(4+4xy+x²y²)=-(2+xy)²
2/1x²+2xy+2y²=(x²+4xy+4y²)/2=(x+2y)²/2
4（x+y）²-25=(2x+2y+5)(2x+2y-5)
x²+xy-3x-3y=x(x+y)-3(x-y)=(x+y)(x-3)
x²-y²-x+1/4=x²-x+1/4-y²=(x-1/2)²-y²=(x-1/2+y)(x-1/2-y)
a²-b²-4ac-4bc=(a+b)(a-b)-4c(a+b)=(a+b)(a-b-4c)
1-a²-2ab-b²==1-(a²+2ab+b²)=1-(a+b)²=(1+a+b)(1-a-b)
2ax-10ay+5by-bx=2a(x-5y)-b(x-5y)=(x-5y)(2a-b)
x²+xy+bx+ax+by+ay=x(x+y)+b(x+y)+a(x+y)=(x+y)(x+a+b)
x²+3x-4=(x+4)(x-1)
x²+5x+6=(x+2)(x+3)
x²-3x-10=(x-5)(x+2)
2x²+x-15=(2x-5)(x+3)

1/4xy³+0.01xy=0.25xy³+0.01xy=0.01xy(25y²+1)
y²-8y+16=(y-4)²
-4-4xy-x²y²=-(2+xy)
2/1x²+2xy+2y²=1/2(x²+4xy+4y²)=1/2(x+2y)²
4（x+y）²-25=(2x+2y-5)(2x+2y+5)
x²+xy-3x-3y=x(x+y)-3(x+y)=(x+y)(x-3)
x²-y²-x+1/4=(x-1/2)²-y²=(x-y-1/2)(x+y-1/2)
a²-b²-4ac-4bc=(a-b)(a+b)-4c(a+b)=(a+b)(a-b-4c)
1-a²-2ab-b²=1-(a+b)²=(1-a-b)(1+a+b)
2ax-10ay+5by-bx=2a(x-5y)-b(x-5y)=(x-5y)(2a-b)
x²+xy+bx+ax+by+ay=x(x+y)+a(x+y)+b(x+y)=(x+y)(x+a+b)
x²+3x-4=(x+4)(x-1)
x²+5x+6=(x+2)(*x+3)
x²-3x-10=(x-5)(x+2)