To find the y-value when \( x = 13 \) in the function \( y = \sqrt{12x + 3} - 9 \), we follow these steps:
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Substitute \( x = 13 \) into the function:
\[ y = \sqrt{12(13) + 3} - 9 \]
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Calculate \( 12(13) \):
\[ 12(13) = 156 \]
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Add 3:
\[ 156 + 3 = 159 \]
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Take the square root of 159:
\[ \sqrt{159} \]
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Subtract 9:
\[ y = \sqrt{159} - 9 \]
Now, we can calculate the approximated value of \( \sqrt{159} \). The square root of 159 is approximately 12.57.
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Calculate \( 12.57 - 9 \):
\[ 12.57 - 9 \approx 3.57 \]
The approximate y-value when \( x = 13 \) is \( 3.57 \), which does not match any of the given choices.
Looking at the options provided:
- 2
- -1
- -5
- -7
None of these correspond to the calculated result. Therefore, it seems there may either be a misinterpretation in the function or an error in the options. If strictly considering the options, none of them fit the y-value derived from the function given.