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

Question

−16
negative 16

−12.5
negative 12.5

−15
negative 15

−13.5

Answer 1

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

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

Calculating \( 18(-4) \):

\[ 18(-4) = -72 \]

Now substitute this back into the equation:

\[ y = -72 - 13 \]

Calculating \(-72 - 13\):

\[ y = -72 - 13 = -85 \]

Therefore, the value of the function when \( x = -4 \) is \( y = -85 \).

None of the provided answer choices (-16, -12.5, -15, -13.5) match this result, indicating that either the equation or the input values might have been miscommunicated. Please verify the values or the equation if needed.