Question

Find the equation in slope-intercept form of the line passing through the points with the given coordinates.(4,2), (4,9)

Answer 1

It is given that the line passes through points (x1, y1)=(4, 2) and (x2, y2)= (4, 9).

The slope of the line can be written as,

`\begin{gathered} m=(y2-y1)/(x2-x1) \\ m=(9-2)/(4-4) \\ m=(7)/(0) \end{gathered}`

So, the slope of the line is undefined. When the slope is undefined, the line passes parallel to the y axis and the equation of the line has the form x=b, where b is a constant.

Since the constant x coordinate of the given points is 4, b=4.

So, the equation of the line is x=4.