What is the value of the function y=18x−13 when x=−4 ?

−16

−12.5

−15

−13.5

1 answer

To find the value of the function \( y = 18x - 13 \) when \( x = -4 \), we can substitute \(-4\) for \(x\):

\[ y = 18(-4) - 13 \]

Calculating \(18(-4)\):

\[ 18 \times -4 = -72 \]

Now substituting that back into the equation:

\[ y = -72 - 13 \]

Calculating \(-72 - 13\):

\[ y = -85 \]

Thus, the value of the function \(y\) when \(x = -4\) is \(-85\). Since \(-85\) is not one of the provided options, it appears that the answer choices may not be referencing this calculation or involve a different equation.

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