+49 Find the number that we can place in the box so that the resulting quadratic is the square of a binomial. \[x^2 + \dfrac{4}{5}x + \boxed{\phantom{000}}\]
I've seen similar problems, but I don't know how to solve them! Help please!
+37146 I think your question is
x2 + 4/5 x + ? We need to 'complete the square' take 1/2 of the x coefficient (2/5) , square it , and add it to the equation
(x2 + 4/5 x + 4/25) then it becomes
(x+2/5)^2
