Q17 of 77 Page 7


Prove that the points (2a, 4a), (2a, 6a), (2a +https://static.philoid.co/ncertusercontent/solutions/user_files/63094/15045/images/extra-7_files/Image2909.gif a, 5a)are the vertices of an equilateral triangle.


PROOF:

Let A(2a, 4a), B(2a, 6a) and C(2a + √3 a, 5a) be the vertices of an equilateral triangle.


⇒ AB = BC = CA.
∴ the vertices are of an equilateral triangle.

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