Solution
Firstly, we need to find the equation of the line passing through the points
W(1, 3) and X(2, 6)
and also the equation of the line passing through the points Y(4, 4), and Z(7, 3)
The line WX is given as
The line YZ is given as
The gradient of WX is 3
The gradient of YZ is -1/3
Since the product of the gradient WX and YZ
Hence WX is perpendicular to YZ