To determine if \( x = -3 \) is a solution to the quadratic equation \( -3x^2 - 9x = 0 \), we can substitute \( -3 \) into the equation and evaluate it.
Let's break down the substitution:
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Substitute \( x = -3 \): \[ -3(-3)^2 - 9(-3) \]
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Evaluate:
- First, calculate \( (-3)^2 \): \[ (-3)^2 = 9 \]
- Then substitute back: \[ -3(9) - 9(-3) \]
- This becomes: \[ -27 + 27 \]
- Which simplifies to: \[ 0 \]
Since substituting \( x = -3 \) results in \( 0 = 0 \), we conclude that \( x = -3 \) is indeed a solution to the equation.
Thus, the correct response is:
Yes, x = -3 is a solution because substituting it back into the equation results in the following: \[ -3(-3)^2 - 9(-3) = 0 \implies 0 = 0 \text{ (True)} \]
This indicates that the first response is the correct reasoning.