Finding derivative of $F'(-2)$

Question

If $F(x)=f(g(x))$, where $f(5) = 8$, $f'(5) = 2$, $f'(−2) = 5$, $g(−2) = 5$, and $g'(−2) = 9$, find $F'(−2)$. I'm totally lost on this problem, I'm assuming to incorporate the Chain Rule. I get $5(5) * 9 = 225$ but I am incorrect.

Update: Thanks guys, I see where I messed up thanks!

Answer 1

We have that $$F'(x) = f'(g(x))g'(x),$$ and since we know $g(-2)$, $g'(-2)$, and $f'(5)$, we can find the final answer of $$F'(-2) = f'(g(-2))g'(-2) = f'(5)\cdot 9 = 18.$$

Answer 2

$F'(x)=f'(g (x))\cdot g'(x) $, by the chain rule. .. I'm getting 18...

Answer 3

The chain rule gives $F'(x)=g'(x)f'(g(x))$. Now just substitute the values \begin{eqnarray*} F'(-2)=\underbrace{g'(-2)}_{9}f'(\underbrace{g(-2)}_{5})=9\underbrace{f'(5)}_{2}=9 \times 2 =\color{red}{18}. \end{eqnarray*}