X^2+1/2x+1/16=4/9 factor the perfect-square trinomial on the left side of the equation. (x + )² = 4/9

The missing number is the square-root of the constant term on the left-hand-side, which equals sqrt(1/16)=1/sqrt(16)=1/4.
Check:
(x+1/4)^2=x^2+2*(1/4)x+(1/4)^2=x^2+x/2+1/16.   ok

x= 1/4

The answer would be a i think

I'm gonna have to say about 13 percent