if lim f(x) = -20, what is the value of lim -8f(x)?

Answer:

160

Explanation:

Step1: Recall limit - constant multiple rule

$\lim_{x\rightarrow a}[cf(x)] = c\lim_{x\rightarrow a}f(x)$

Step2: Identify values of $c$ and $\lim_{x\rightarrow a}f(x)$

Here $c=- 8$, $\lim_{x\rightarrow5}f(x)=-20$

Step3: Calculate the limit

$\lim_{x\rightarrow5}[-8f(x)]=-8\times\lim_{x\rightarrow5}f(x)=-8\times(-20) = 160$