(2x+4y)x(X+4y-6z)= {in prima si a doua paranteza il dam factor comun pe 2}
=[2(x+2y)]x[X+2(2y-3z)]=
=(2x17)x(X+2x2x4)=
=34x(X+16)=
=34x+544=
X=544:34
X=16
