Question

are points (2,3),(-4,5),(3-5) in st. line
want a simple reason medal for easy and best reason

Answer 1

find the equation of the line which passes through the first 2 points first
then, apply the second point on that equation, if it satisfies the equation, then they are on the straight line.

Answer 2

Put them out on a plane and see if you can draw a straight line through two points that should then contain all the three points. If they don't, then they are not on a straight line.

Answer 3

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