Question

A line has a slope of 1 and passes through the point (4, 20) . What is its equation in slope -intercept form?

Answer 1

`(\stackrel{x_1}{4}~,~\stackrel{y_1}{20})\hspace{10em} \stackrel{slope}{m} ~=~ 1 \\\\\\ \begin{array} \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}{20}=\stackrel{m}{ 1}(x-\stackrel{x_1}{4}) \\\\\\ y-20=x-4\implies {\Large \begin{array}{llll} y=x+16 \end{array}}`