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Question
Show that x = −2 is a solution of 3x2 + 13x + 14 = 0.
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Solution
Given that the equation 3x2 + 13x + 14 = 0
`3x^2 + 7x + 6x + 14 = 0`
`x (3x + 7) + 2 (3x + 7) = 0`
`(3x + 7) (x + 2) = 0`
(3x + 7) = 0
`x = (-7)/3`
or
(x + 2) = 0
x = - 2
Therefore, x = -2 is the solution of given equation.
Hence, proved.
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