It equals 1 + 3z and, unless you know the value of z, you are not going to be any the wiser as to its value.
That depends what the value of p is.
y - 1
-1
4
It is 1
The value of x is -21.
The value of x is 1
x=4
It is an equation and the value of x is 1
7
The discriminant is 1.