To find the y-coordinate of the parabola given the equation \( y = 5x^2 + 8x + 9 \) when \( x = -3 \), we can substitute \(-3\) for \(x\) in the equation:
\[ y = 5(-3)^2 + 8(-3) + 9 \]
Calculating step-by-step:
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Calculate \((-3)^2\): \[ (-3)^2 = 9 \]
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Multiply by 5: \[ 5 \times 9 = 45 \]
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Calculate \(8 \times (-3)\): \[ 8 \times (-3) = -24 \]
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Now substitute these values back into the equation: \[ y = 45 - 24 + 9 \]
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Combine the values: \[ y = 45 - 24 = 21 \] \[ y = 21 + 9 = 30 \]
Thus, the y-coordinate when \( x = -3 \) is \( y = 30 \). Therefore, the final result is:
\[ (-3, 30) \]