To solve the equation \( 3x^2 - 20 = 7 \) by factoring, we first rearrange it:
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Subtract 7 from both sides: \[ 3x^2 - 20 - 7 = 0 \] Simplifying gives: \[ 3x^2 - 27 = 0 \]
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Factor out the common factor (which is 3): \[ 3(x^2 - 9) = 0 \]
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Now, recognize that \( x^2 - 9 \) is a difference of squares: \[ x^2 - 9 = (x - 3)(x + 3) \]
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Thus, our equation can be factored as: \[ 3(x - 3)(x + 3) = 0 \]
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Setting each factor equal to zero gives us the solutions: \[ x - 3 = 0 \quad \Rightarrow \quad x = 3 \] \[ x + 3 = 0 \quad \Rightarrow \quad x = -3 \]
So the correct solutions are \( x = 3 \) and \( x = -3 \).
From the provided responses, the correct answer is:
x = −3, x = 3 (x equals negative 3, x equals 3).