Answer
$-9$ and $ y=-9x-5$
Work Step by Step
Now, $ m_{\tan}=\lim_\limits{ h\to 0} \dfrac{f(-1+h)-f(-1)}{h}$
or, $=\lim_\limits{ h\to 0} \dfrac{(h-1)^2-7(h-1)-4-(-1)^2+7(-1) +4}{h}$
or, $=\lim_\limits{ h\to 0} \dfrac{h^2-9h}{h}$
or, $=-9$
The equation of a line is: $ y=mx+c $
Now, $ y-4=-9(x+1) \implies y=-9x-5$
