Question

The three points (2, - 4), (4, - 2), (7,1)​

Answer 1

I am assuming that this your question :

Consider the points P(2,−4);Q(4,−2) and R=(7,1). The points P,Q,R.

Answer:

P(2,−4)Q(4,−2)R(7,1)

Check for option A

PQ=2 $\sqrt{2}$    

​QR=3  $\sqrt{2}$

RP=5  $\sqrt{2}$  

Not an equilateral Δ

Now, equation of line of PQ

( x−4 ) ( 1 ) = y + 2

x − y = 6

Satisfies point R

Hence PQR are collinear point.

Answer 2

Answer:

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