Need answering these five geometry questions i need answers

Can any one me with the answers to these questions asap?

Plz determine whether the polynomial is a difference of squares and if it is, factor it. y2 – 196 is a difference of squares: (y + 14)2 is a difference of squares: (y – 14)2 is a difference of squares: (y + 14)(y – 14) is not a difference of squares

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10