Zero
Undefined
Positive
Negative ?

Zero

Step-by-step explanation:

The line is a straight line going across the x axis so there is no change in y so there is no slope because slope is the change of y.

none of the above.

for one of the equations to be used in the process, there has to be a term in the equation since squared is .

since there is only a term in the first equation, we cannot derive a from completing the square.

solving with completing the square