SOLUTION: how do you solve this equation by completing the sqaure?{{{x^2+6x-40=0}}}

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Question 82350: how do you solve this equation by completing the sqaure?x%5E2%2B6x-40=0
Found 2 solutions by stanbon, scott8148:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve this equation by completing the sqaure:
x^2+6x-40=0
x^2+6x+9-40-9=0
(x+3)^2=49
x+3 = 7 or x+3 = -7
x=4 or x=-10
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Cheers,
Stan H.

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
move constant terms to right side ... x%5E2%2B6x=40
divide the coefficient of the x term by 2, square it, and add to both sides ... x%5E2%2B6x%2B3%5E2=40%2B3%5E2

factor the quadratic ... %28x%2B3%29%5E2=49

take the square root of both sides ... x+3=7 and x+3=-7 ... so x=4 and x=-10