+0

0
52
2
+49

Find the number that we can place in the box, so that the resulting quadratic is the square of a binomial.
$$x^2 + \dfrac{4}{5}x + \boxed{\phantom{000}}$$

:D

Apr 14, 2020

#1
+1

I learned this!  (x + 4/5)^2 = x^2 + 4/5*x + 16/25, so 16/25 goes in the box.

Apr 14, 2020
#2
+109524
+1

Sorry guest but that is not correct.

half of 4/5 is 2/5

(2/5)^2 = 4/25

$$(x+\frac{2}{5})^2 = x^2+2*\frac{2x}{5}+(\frac{2}{5})^2$$

Melody  Apr 14, 2020