Question

find the slope of the following: (-1, 8) and (12, -5)

Answer 1

The rule of the slope of the line is

$m=\frac{y2-y1}{x2-x1}$

(x1, y1) and (x2, y2) are two points on the line

Since the line passes through points (-1, 8) and (12, -5), then

x1 = -1 and y1 = 8

x2 = 12 and y2 = -5

Substitute theses values in the rule above to find m

$m=\frac{-5-8}{12--1}=\frac{-13}{12+1}=\frac{-13}{13}=-1$

The slope of the line is -1