Question

How do you write the equation of the vertical line passing through the point (-2,1)?

Answer 1

x = -2

Explanation:

This is a special case of the equation of a line in that it's slope is undefined and it is parallel to the y-axis. The line passes through all points in the plane with the same x-coordinate and has equation
y = c where c is the value of the x-coord.
In this case the line passes through (-2 ,1) and it's equation is x = -2
graph{0.001y-2=x [-10, 10, -5, 5]}

Answer 2

`x = -2`

Explanation:

All vertical lines only have an `x-`intercept, where they cross the `x`-axis. They are therefore written in the from `x = .....`

Seeing that the x-value of the point is -2, it means that this is the value of `x` we need to use for the equation of the vertical line.