Question

Given f, of, x, equals, minus, 3, x, squared, minus, 6, xf(x)=−3x
2
−6x, find f, of, minus, 4f(−4)

Answer 1

To find \( f(-4) \) for the function \( f(x) = -3x^2 - 6x \), we need to substitute \(-4\) into the function.

So,

\[
f(-4) = -3(-4)^2 - 6(-4)
\]

Now we calculate each term:

1. Calculate \((-4)^2\):
\[
(-4)^2 = 16
\]

2. Substitute back into the function:
\[
f(-4) = -3(16) - 6(-4)
\]

3. Calculate \(-3(16)\):
\[
-3(16) = -48
\]

4. Calculate \(-6(-4)\):
\[
-6(-4) = 24
\]

5. Combine the results:
\[
f(-4) = -48 + 24 = -24
\]

Thus, \( f(-4) = -24 \).