SOLUTION: X^2+13x+39=0

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Question 1083058: X^2+13x+39=0
Found 2 solutions by Alan3354, addingup:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Thx for letting us know.

Answer by addingup(3677) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+13x+39 = 0
x^2+13x = -39
The coefficient of x is 13. Divide it by 2 and you get 13/2. Square it(13/2)^2 = 169/4
Now add it to both sides:
x^2+13x+169/4 = -39+169/4
x^2+13x+169/4 = 13/4
Factor the left side
(x+13/2)^2 = 13/4
sqrt(x+13/4)^2 = sqrt(13/4)
x+13/2 = (sqrt13)/2
x = [(sqrt13)-13]/2 or x = [(-sqrt13)-13]/2
x = -4.7 or x = -8.3