What number can we place in the box to make the quadratic below the square of a binomial: \[ x^2 + \dfrac{5}{3}x + \boxed{\phantom{000}}. \]
\( \[ x^2 + \dfrac{5}{3}x + \boxed{\phantom{000}}. \]\)
Take 1/2 of 5/3 = 5/6 ....square it = 25/36
So
x^2 + 5/3x + 25/36 factors as
(x + 5/6 )^2
So..... 25/36 is what we need
