Question

What number needs added to the equation x^2+22x=9 to complete the square

Answer 1

X^2 + 22x + 121 = 0  is a perfect  square
So we need to add 130 to the left side,

Answer 2

121

x^2 + 22 x = 9

following the equation $( \frac{b}{2} ) ^{2}$

you should divide 22 by 2, and then square it, which results in 121