\(a,\\ c1:=\left(2xy+2x\right)+\left(z+yz\right)=2x\left(y+1\right)+z\left(y+1\right)\\ c2:=\left(2xy+yz\right)+\left(z+2x\right)=y\left(2x+z\right)+\left(z+2x\right)\)
\(d,\\ c1:=\left(x^2-3x\right)+\left(xy-3y\right)=x\left(x-3\right)+y\left(x-3\right)\\ c2:=\left(x^2+xy\right)-\left(3x+3y\right)=x\left(x+y\right)-3\left(x+y\right)\)