1. Finding Lengths on the Coordinate Plane Horizontal & Vertical Lines on a Coordinate Plane

2. Finding Lengths of Horizontal Lines on a Coordinate Plane
Horizontal Lines have the same y-coordinate
Example: (2, 1) and (5, 1)
If points are on the opposite sides of the y-axis, then they have different signs.
Example: (2, 1) and (-3, 1)

3. Horizontal - Points on the Same Side
Points on the same side of the y-axis
Same side = same sign!
To find the length
Count the distance between the x-coordinates (or subtract them)
Example: (2, 1) and (5, 1)
The distance from 2 to 5 = 3, so the distance is 3 units.
5 – 2 = 3

4. Horizontal - Points on the Opposite Side
Points on the opposite side of the y-axis
Opposite side = Opposite signs
To find the length
Find the Absolute Value of each of the x-coordinates
Add the two absolute values
Example: (2, 1) and (-3, 1)
2 and -3 are on opposite sides. Absolute values are 2 & 3
, so the distance between the points is 5 units.

5. Finding Lengths of Vertical Lines on a Coordinate Plane
Vertical Lines have the same x-coordinate
Example: (2, 4) and (2, 9)
If points are on the opposite sides of the x-axis, then they have different signs.
Example: (-5, 4) and (-5, -2)

6. Vertical - Points on the Same Side
Points on the same side of the x-axis
Same side = same sign!
To find the length
Count the distance between the y-coordinates (or subtract them)
Example: (-1, 6) and (-1, 4)
The distance from 4 to 6 = 2, so the distance is 2 units.
6 – 4 = 2

7. Vertical - Points on the Opposite Side
Points on the opposite side of the x-axis
Opposite side = Opposite signs
To find the length
Find the Absolute Value of each of the y-coordinates
Add the two absolute values
Example: (5, 4) and (5, -2)
Since 4 is a positive and 2 is a negative, the points are on opposite sides of the axis is 4 + 2
4 + 2 = 6, so the distance between the two points is 6 units

8. Lines and No lines Neither Horizontal or Vertical
Points with different x-coordinates and different y-coordinates do not form a horizontal or vertical line.
Example: (-3, 2) and (5, 6)
Lie on the X-axis
Points that lie on the x-axis and have a y-coordinate of 0.
Example: (8, 0) and (7, 0)
Lie on the Y-axis
Points that lie on the y-axis and have an x-coordinate of 0.
Example: (0, 4) and (0, 10)