What is the y-intercept of a graph with the points (-1, -2) and (4, 6)?

Apr 30, 2016

$y$-intercept $= - \frac{2}{5}$

Explanation:

The run of $x$ is $5$ and the rise of $y$ is $8$

The slope is

$\text{slope" = "rise"/"run} = \frac{8}{5}$

You have

$y = \frac{8}{5} x$

Then if you put $\left(4 , 6\right)$ at the equation above,

$6 = \frac{32}{5}$

To make the equation true, you should subtract $\frac{2}{5}$

$y = \frac{8}{5} x - \frac{2}{5}$