9th grade algebra 1 ?

what number would you add to complete the square?

x² + 12x

In equations like
ax^2 + bx + c^2
if you want to make it square, b has to be equal to 2ac

Therefore in this equation c has to be 6 and the number you have to add is 36

At a constant it will take one hour to travel 32 mi.at that speed it will take 1/2 hr to travel the remaining 16 mi.it will take 1+1/2 hr to travel the 48mi @ 32mph.so 1 hr = 60 min& 1/2 hr = 30 min1+1/2 hr = 90 min.there are 60s in each 90 × 60 = 3600 seconds.the real question seriously is he why are they driving so slow? ! lol.