Respuesta :

Step-by-step explanation:

a) gradient= y2-y1/x2-x1

gradient of AB:

gradient=-4-1/2-3

=-5/-1

=5

gradient of BC:

=-5+4/7-2

=-1/5

b) as the priduct of both gradient is -1 ,both lines are perpendicular.

c) as we have seen lines are perpendicular so it is a right angled triangle.