Answer
$f'(a)=\lim \limits_{h \to 0}-2$, which equals to $-2$.
$f'(-1)=-2$
Work Step by Step
The algebraic derivative of a function can be described as:
$f'(a)=\lim \limits_{h \to 0}\frac{f(a+h)-f(a)}{h}$
Here, $f(a)=-2a+4$
By substituting, we get:
$\frac{-2(a+h)+4-(-2a+4)}{h}=\frac{-2a-2h+4+2a-4}{h}=\frac{-2h}{h}=-2$
$f'(a)=\lim \limits_{h \to 0}-2$, which equals to $-2$.
$f'(-1)=-2$
