Question

Determine the slope and vertical intercept of the following linear function below

X/-4,-2,0,2,4
Y/-114,-60,-6,48,102
what is the slope & what is the vertical intercept ( as an ordered pair ) ?

Answer 1

to get the slope of it, we simply need two points off the table, say (-4,-114) and (2,48). Recall that the y-intercept, where the graph intercepts the y-axis, when that happens x = 0, so is right there on the table already.

`\bf \begin{array}{rrll} x&y\\ \cline{1-2} -4&-114\\ -2&-60\\ 0&-6&\leftarrow y-intercept\\ 2&48\\ 4&102 \end{array}~\hfill (\stackrel{x_1}{-4}~,~\stackrel{y_1}{-114})\qquad (\stackrel{x_2}{2}~,~\stackrel{y_2}{48})`

`\bf slope\implies \cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{48-(-114)}{2-(-4)}\implies \cfrac{48+114}{2+4}\implies \cfrac{162}{6}\implies 27 \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ ~\hfill \left(\stackrel{slope}{27}~~,~~\stackrel{y-intercept}{-6} \right)~\hfill`