Question

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

Answer 1

The options are
-12.5
-16
-15
-13.5

Answer 2

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

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

Now, calculate \( 18 \times -4 \):

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

Now, substitute this value back into the equation:

\[
y = -72 - 13
\]

Now, calculate \(-72 - 13\):

\[
y = -85
\]

Thus, the value of the function when \( x = -4 \) is

\[
\boxed{-85}
\]

Answer 3

Let’s re-evaluate the calculation given the options provided.

We have the function \( y = 18x - 13 \) and we need to find the value when \( x = -4 \).

1. Substitute \(-4\) for \( x \):

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

2. Calculate \( 18 \times -4 \):

\[
y = -72 - 13
\]

3. Now, simplify:

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

It appears that the calculated value of \( -85 \) is not among the options you provided. Given the options (-12.5, -16, -15, -13.5), it seems there might have been a misunderstanding about the value of \( x \) or the function itself.

Double check the question or options in case of an error. Would you like to check any other values or details?