Question
Show that $x = -2$ is a solution of $3x^2 + 13x + 14 = 0.$
✓
Answer
Given that the equation of $3x^2 + 13x + 14 = 0$
$3x^2 + 7x + 6x + 14 = 0$
$x(3x + 7) + 2(3x + 7) = 0$
$(3x + 7)(x + 2) = 0$
$(3x + 7) = 0$
$\text{x}=\frac{-7}{3}$
Or $(x + 2) = 0$
$x = -2$
Therefore, x = 2 is the solution of given equation.
Hence, proved.
$3x^2 + 7x + 6x + 14 = 0$
$x(3x + 7) + 2(3x + 7) = 0$
$(3x + 7)(x + 2) = 0$
$(3x + 7) = 0$
$\text{x}=\frac{-7}{3}$
Or $(x + 2) = 0$
$x = -2$
Therefore, x = 2 is the solution of given equation.
Hence, proved.
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