Question

Prove that the points (2, – 2), (–3, 8) and (–1, 4) are collinear.

Answer 1

Concept:
Application:

$\therefore \Delta =\frac{1}{2}|2\times (8-4)+-3(4+2)+(-1)(-2-8)|$

$\Rightarrow \Delta =\frac{1}{2}|(8-18+10)|$

$\Rightarrow \Delta =\frac{1}{2}|18-18|=0$

Hence, given points are collinear.