Question

What is the equation of the line that passes through the point (-1,-1) and has a slope of -4?

Answer 1

`(\stackrel{x_1}{-1}~,~\stackrel{y_1}{-1})\hspace{10em} \stackrel{slope}{m} ~=~ - 4 \\\\\\ \begin{array}c \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{(-1)}=\stackrel{m}{- 4}(x-\stackrel{x_1}{(-1)}) \implies y +1= -4 (x +1) \\\\\\ y+1=-4x-4\implies {\LARGE \begin{array}{llll} y=-4x-5 \end{array}}`