Question
Solve the following quadratic equation:$4x^2 - 9x = 100$
✓
Answer
$4x^2 - 9x = 100$
$\Rightarrow 4x^2 - 9x - 100 = 0$
$\Rightarrow 4x^2 - 25x + 16x - 100 = 0$
$\Rightarrow x(4x - 25) + 4(4x - 25) = 0$
$\Rightarrow (4x - 25)(x + 4) = 0$
$\Rightarrow 4x - 25 = 0 or x + 4 = 0$
$\Rightarrow\text{x}=\frac{25}{4}$ or x = -4
Hence, $\frac{25}{4}$ and -4 are the roots of the equation $4x^2 - 9x = 100$
$\Rightarrow 4x^2 - 9x - 100 = 0$
$\Rightarrow 4x^2 - 25x + 16x - 100 = 0$
$\Rightarrow x(4x - 25) + 4(4x - 25) = 0$
$\Rightarrow (4x - 25)(x + 4) = 0$
$\Rightarrow 4x - 25 = 0 or x + 4 = 0$
$\Rightarrow\text{x}=\frac{25}{4}$ or x = -4
Hence, $\frac{25}{4}$ and -4 are the roots of the equation $4x^2 - 9x = 100$
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