Question
Solve the following quadratic equation:$15x^2 - 28 = x$
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Answer
1$5x^2 - 28 = x$
$\Rightarrow 15x^2 - x - 28 = 0$
$\Rightarrow 15x^2 - 21x + 20x - 28 = 0$
$\Rightarrow 3x(5x - 7) + 4(5x - 7) = 0$
$\Rightarrow (5x - 7)(3x + 4) = 0$
$\Rightarrow 5x - 7 = 0$ or $3x + 4 = 0$
$\Rightarrow\text{x}=\frac{7}{5}$ or $\text{x}=\frac{-4}{3}$
Hence, $\frac{7}{5}$ and $\frac{-4}{3}$ are the roots of the equation $15x^2 - 28 = x$
$\Rightarrow 15x^2 - x - 28 = 0$
$\Rightarrow 15x^2 - 21x + 20x - 28 = 0$
$\Rightarrow 3x(5x - 7) + 4(5x - 7) = 0$
$\Rightarrow (5x - 7)(3x + 4) = 0$
$\Rightarrow 5x - 7 = 0$ or $3x + 4 = 0$
$\Rightarrow\text{x}=\frac{7}{5}$ or $\text{x}=\frac{-4}{3}$
Hence, $\frac{7}{5}$ and $\frac{-4}{3}$ are the roots of the equation $15x^2 - 28 = x$
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