Question

x2 − 16x + ____

Answer 1

http://openstudy.com/users/andremoon#/users/andremoon/updates/4e4d88aa0b8b9588049f9ce5

Answer 2

answered

Answer 3

If you're looking to complete the square, then take half of -16 to get -8 and square that to get 64. Add and subtract this (so the expression stays equal) to the expression.

If you want to force that expression to be a perfect square (ie it may change), then simply add 64 in the blank.