Just remember the syllables PEMDAS which stand for Parentheses, Exponents, Multiplication, Division, Addition and Subtraction. If you can’t remember it, just write it on the side of your paper. But make sure to use it in that order.
When completing the square, you take the value after x^2 which is 14 and divide it by 2 which equals 7 for which you then square that number which 7 times 7 = 49
