Knowledge Check

The functions $f$ and $g$ are defined as follows.
\[
f(x)=-3 x-1 \quad g(x)=2 x^{2}-3 x
\]

Find $f(7)$ and $g(-5)$.
Simplify your answers as much as possible.
\[
\begin{array}{l}
f(7)=-22 \\
g(-5)=\square
\end{array}
\]

Answer

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Answer

So, the final answers are $f(7) = -22$ and $g(-5) = \boxed{65}$.

Steps

Step 1 ：The functions $f$ and $g$ are defined as follows: $f(x)=-3 x-1$ and $g(x)=2 x^{2}-3 x$.

Step 2 ：To find $f(7)$, we substitute $x$ with $7$ in the function $f(x)$, which gives us $f(7)=-22$.

Step 3 ：To find $g(-5)$, we substitute $x$ with $-5$ in the function $g(x)$.

Step 4 ：After substituting, we get $g(-5) = 65$.

Step 5 ：So, the final answers are $f(7) = -22$ and $g(-5) = \boxed{65}$.