Q3 of 112 Page 150

Determine if the following set of points are collinear or not.
(4, 3), (1, 2) and (–2, 1)

(4, 3), (1, 2) and (–2, 1)

Let A (4, 3) B (1, 2) and C (–2, 1) be the vertices of triangle.

Area of triangle =

x₁ = 4, x₂ = 1 and x₃ = –2

y₁ = 3, y₂ = 2 and y₃ = 1

⇒

Therefore, the given points are collinear.

Vertices of the triangles taken in order and their areas are given below. In each of the following find the value of a.

Vertices: (a, a), (4, 5), (6, –1)

Area (in sq. units): 9

Vertices of the triangles taken in order and their areas are given below. In each of the following find the value of a.

Vertices: (a, –3), (3, a), (–1,5)

Area (in sq. units): 12

Determine if the following set of points are collinear or not.

(–2, –2), (–6, –2) and (–2, 2)

Determine if the following set of points are collinear or not.

, (6, –2) and (–3, 4)

Determine if the following set of points are collinear or not.(4, 3), (1, 2) and (–2, 1)