Question

Write an equation of the line that passes through (0, 4) and (0, -3)

Answer 1

`x=0`

Explanation:

1. So first of all we need the slope of the line we are trying to find
2. We get the slope by using the following formula
   `slope=(y_2-y_1)/(x_2-x_1)`
3. So when you have two pairs of points, it will be
   `(x_1,y_1)` and
   `(x_2,y_2)`
4. so our points are;
5. (0,4) the first point, so
   `x_1=0,y_1=4` and
6. (0.-3) the second point, so
   `x_2=0,y_2=-3`
7. Put this in our equation
   `slope=((-3)-(4))/((0)-(0))=(-7)/(0)`
8. Oh no, that can't be right, any number divided by zero is undefined, meaning can't be answered. So this line has no slope
9. So how do we know the equation? Remember,
10. (a) if the line is horizontal, then the slope is 0,
11. (b) if the line is vertical then the slope is undefined
12. So our line is vertical, meaning it is an equation of x
13. If it were horizontal it would be an equation of y
14. So vertical, it is
    `x=??`
15. How do we know what x equals? Just look at our points (0,4) and (0,-3)
16. For both of them
    `x=0` and this is our equation!

Answer 2

Answer: Slope is undefined. x=0

slope calculation: -3-4/0-0 = -7/0 and anything divided by 0 is undefined

the x value in the coordinates is 0 so it’s x=0 line.

vertical lines always have undefined slopes