Question 480775
complete the square.

x^2+16x=0
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x^2 + 16x + 8^2 = 8^2
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(x+8)^2 = 64
----
(x+8)^2-64 = 0
Factof:
[(x+8)-8][(x+8)-8] = 0
----
x+8-8 = 0 or x+8+8 = 0
x = 0 or x = -16
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Cheers,
Stan H.