Q1 of 23 Page 226

Prove that the points (1, 8), (2, 5), (3, 7) are on the same line.

The three points are (1, 8) ,(2, 5) ,(3, 7)


Slope of First two points


Slope of First two points = - 3


The Equation of line between first two points :


y - 8 = - 3(x - 1)


⇒ y - 8 = - 3x + 3


⇒ 3x + y = 11


We put the point (3, 7) in the above equation.


On solving we will find the point doesn’t satisfy the equation.


Hence the three points doesn’t lie on a straight line.


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