If the points A(1, 2), B(0, 0) and C(a, b) are collinear, then -Maths 9th

1 Answer

Answer :

(a) - 2For three points to be collinear, area of the triangle formed by the three points should be equal to zero, i.e.\(rac{1}{2}\) [k(3k – 1) + 2k(1 – 2k) + 3(2k – 3k)] = 0⇒ \(rac{1}{2}\) [3k2 – k + 2k – 4k2 – 3k] = 0⇒ k2 + 2k = 0 ⇒ k = 0 or –2 Neglecting k = 0, as then (k, 2k) and (2k, 3k) will be the same point, we take k = –2.

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