Question
Solve the following quadratic equation:
$9x^2 + 6x + 1 = 0$
$9x^2 + 6x + 1 = 0$
✓
Answer
$9x^2 + 6x + 1 = 0$
$\Rightarrow 9x^2 + 3x + 3x + 1 = 0$
$\Rightarrow 3x(3x + 1) + 1(3x + 1) = 0$
$\Rightarrow (3x + 1)(3x + 1) = 0$
$\Rightarrow (3x + 1)^2 = 0$
$\Rightarrow 3x + 1 = 0$
$\Rightarrow\text{x}=\frac{-1}{3}$ (repeated root)
$\Rightarrow 9x^2 + 3x + 3x + 1 = 0$
$\Rightarrow 3x(3x + 1) + 1(3x + 1) = 0$
$\Rightarrow (3x + 1)(3x + 1) = 0$
$\Rightarrow (3x + 1)^2 = 0$
$\Rightarrow 3x + 1 = 0$
$\Rightarrow\text{x}=\frac{-1}{3}$ (repeated root)
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