On complete intersections and transversality at a point?

Let $F_1,F_2$ be degree $1$ and $F_3$ be degree $2$ in $\mathbb Z[x_1,\dots,x_4]$. Let there be an unique common integer to $F_i$. Let them be algebraically independent of a fourth polynomial $G$ which also has the same common integer root.

1. Is it possible for the system to not form a complete intersection at the integer root? Can you give an example?

2. If it forms a complete intersection then what are the conditions for the root to be not a transversal point?