a)\(4x^2+x=x\left(4x+1\right)\)
b)\(3x-9y=3\left(x-3y\right)\)
c)\(5\left(x-y\right)-x\left(x-y\right)=\left(5-x\right)\left(x-y\right)\)
d)\(4\left(2x-y\right)-x\left(y-2x\right)=-4\left(y-2x\right)-x\left(y-2x\right)=\left(-4-x\right)\left(y-2x\right)\)
e)\(\left(2x+1\right)^2+2\left(2x+1\right)=\left(2x+1\right)\left(2x+1+2\right)=\left(2x+1\right)\left(2x+3\right)\)
f)\(y\left(x+y\right)-y-x=y\left(x+y\right)-\left(x+y\right)=\left(y-1\right)\left(x+y\right)\)
g)\(2y\left(x-y\right)^2+x\left(y-x\right)^2=2y\left(y-x\right)^2+x\left(y-x\right)^2=\left(2y+x\right)\left(y-x\right)^2\)
h)
h)(x-2)-(x-2)^2=(x-2)(1-x-2)=(x-2)(x-1)
i)x(x-3)-2x+6=x(x-3)-2(x-3)=(x-3)(x-2)
