How do you write the equation of a line through points (-1,4), (-1, 7.2)?

1 Answer
Jun 25, 2018

See below for an explanation!!

Explanation:

The line is a vertical line at #x=-1#. To prove this, we'll find the slope. The formula for this is

#(y_2-y_1)/(x_2-x_1)#

where #(x_1,y_1)# is #(-1,4)# and #(y_1,y_2)# is #(-1,7.2)#.Let's put in values and find the slope:

#(7.2-4)/(-1-(-1))=3.2/(-1+1)=3.2/0#

We can't divide by 0! What does this mean? The slope is undefined, so the line will be vertical. The two points that the line passes through are located at the x-value of #-1#. Therefore, the equation of the line is #x=-1#.

Hope this helped!