Answer:
or 
Step-by-step explanation:
step 1
Find the slope of the line
The formula to calculate the slope between two points is equal to

we have the ordered pairs
(3,-5) and (1,-9)
substitute the values



step 2
Find the equation in point slope form

Analyze two cases
<em>First case</em>
we have


substitute

<em>Second case</em>
we have


substitute

Note: The equation of the line in point slope form varies according to the point you choose, in contrast to the slope-intercept form
Its 0 because the slope would be one if it was a positive line and itd go up and across one unitl and it is undefined if it is parallel to the y axis
3 times. Draw a line 1 unit up, and you can see that there are 3 intersections.