Question

9. Show that the following sets of
points are collinear
i) (2,5), (4,6) and (8,8)
ii) (1,-1), (2, 1) and (4,5)
​

Answer 1

Step-by-step explanation:

Formula:

Area of triangle =

2

1

[x

1

(y

2

−y

3

)+x

2

(y

3

−y

1

)+x

3

(y

1

−y

2

)]

If the area of a triangle is zero, then the points are collinear.

Given,

A(2,5),B(4,6),C(8,8)

Area of △ABC=

2

1

[2(6−8)+4(8−5)+8(5−6)]

=

2

1

[−4+12−8]

=0sq.units

Hence the given points are collinear