To find the y-coordinate of the parabola given by the equation \( y = 5x^2 + 8x + 9 \) when \( x = -3 \), we need to substitute \( -3 \) for \( x \) in the equation.
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Start with the equation: \[ y = 5x^2 + 8x + 9 \]
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Substitute \( x = -3 \): \[ y = 5(-3)^2 + 8(-3) + 9 \]
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Calculate \( (-3)^2 \): \[ (-3)^2 = 9 \]
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Substitute back into the equation: \[ y = 5(9) + 8(-3) + 9 \] \[ y = 45 - 24 + 9 \]
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Simplify the equation: \[ y = 45 - 24 + 9 = 21 + 9 = 30 \]
Therefore, the y-coordinate when \( x = -3 \) is \( 30 \).
So the answer is: \[ (-3, 30) \]
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