Question
Solve the following quadratic equation: $3x^2 - 243 = 0$
✓
Answer
$3x^2 - 243 = 0$
$\Rightarrow 3(x^2 - 81) = 0$
$\Rightarrow x^2 = 81$
$\Rightarrow\text{x}=\pm\sqrt{81}=\pm9$
$\Rightarrow x = 9, -9$
Hence $9$ and $-9$ are the roots of the equation $3x^2 - 243 = 0$
$\Rightarrow 3(x^2 - 81) = 0$
$\Rightarrow x^2 = 81$
$\Rightarrow\text{x}=\pm\sqrt{81}=\pm9$
$\Rightarrow x = 9, -9$
Hence $9$ and $-9$ are the roots of the equation $3x^2 - 243 = 0$
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