Question

question 11
find the equation of a line containing the following points. write the equation in slope - intercept form.
(-1, 1) and (-1, -2)
question help: video written example post to forum

Explanation:

Step1: Calculate the slope

The slope formula is $m=\frac{y_2-y_1}{x_2-x_1}$. Substitute $(x_1,y_1)=(-1,1)$ and $(x_2,y_2)=(-1,-2)$:
$m=\frac{-2-1}{-1-(-1)}=\frac{-3}{0}$
This is undefined, so it's a vertical line.

Step2: Identify vertical line equation

Vertical lines have the form $x=a$, where $a$ is the constant x-value of all points on the line. Both points have $x=-1$.

Answer:

$x=-1$