2y+2+2z and 2 (y+z) are these expressions equivalent

Also 6x (x) and 6x to the 2nd

no,

2y+2+2z has 3 terms and 2 (y+z) has only two terms, you want:

2y+2+2z = 2 (y + 1 + z)

and yes,

6x(x) = 6x^2