I need to know the answer to the two question

Question 1:

78 - 5 - 7

Question 2:

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

probably .5

i can on others if necessary.