
John R. answered 03/04/13
John R: Math, Science, and History Teacher
The follow steps demonstrate how to complete the square to find the solution to the problem
4n2 + 4n + 36 = 0 Given
4n2 + 4n= -36 Subtract 36 from each side
n2 + n = -9 Divide each side by 4
n2 + n + 1/4 = - 9 + 1/4 Add (b/(2a))2 to each side. (Since b and a are each 4, b/(2a) is 1/2)
n2 + n + 1/4 = -35/4 Simplify the right side
(n + 1/2)2 = -35/4 Factor the left side into the perfect square (variable + b/(2a))
n + 1/2 = +/- sqrt(-35/4) Take the square root of both sides
n + 1/2 = +/- sqrt(35)/2*i Simplify the right side
n = -1/2 +/- sqrt(35)/2*i Subtract 1/2 from each side