Perpendicular lines have slopes that are opposite reciprocals of one another. If the slopes of two lines are opposite reciprocals, their product is - 1. Therefore, to determine if the lines are perpendicular or not, we need to find their slopes using the Slope Formula.
Line
Points
y_2-y_1/x_2-x_1
Slope
Simplified Slope
XY
( 4,1) & ( 5,3)
3- 1/5- 4
2/1
2
YZ
( 5,3) & ( 6,2)
2- 3/6- 5
- 1/1
- 1
We will determine if XY and YZ are perpendicular by multiplying their slopes.
2(- 1)=- 2
Since the product of the slopes does not equal -1, the lines are not perpendicular.
