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Question
Show that x = −3 is a solution of x2 + 6x + 9 = 0.
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Solution
Given that the equation x2 + 6x + 9 = 0.
`x^2 + 3x + 3x + 9 = 0`
x (x+3) + 3 (x+3) = 0
(x + 3) (x+3) = 0
(x + 3)2 = 0
Square root both side, we get
(x+3) = 0
x = -3
Therefore, x = -3 is the solution of given equation.
Hence, proved.
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