MCQ
The triangle joining the points $P(2, 7)$, $Q(4, -1)$, $R(-2, 6)$ is
  • A
    Equilateral triangle
  • Right-angled triangle
  • C
    Isosceles triangle
  • D
    Scalene triangle

Answer

Correct option: B.
Right-angled triangle
b
(b) Since $PQ = \sqrt {68} ,\,\,PR = \sqrt {17} ,\,\,QR = \sqrt {85} $

$\therefore \,\,P{Q^2} + P{R^2} = Q{R^2}$, i.e. right angled triangle.

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