4.(i)    By giving a counter example, show that the following statement is not true.
   (i) p: If all the angles of a triangle are equal, then the triangle is an obtuse angled triangle.

Answers (1)

We know, Sum of all the angles of a triangle = 180^{\circ}

If all the three angles are equal, then each angle is 60^{\circ}

But 60^{\circ} is not an obtuse angle, and hence none of the angles of the triangle is obtuse.

Hence the triangle is not an obtuse-angled triangle.

Hence the given statement is not true.