Name each of the following triangles in two different ways: (you may judge the nature of the angle by observation).
(a)
(b)
(c)
(d)
(e)
(f)
(a) Acute-angled and isosceles triangle
As in this figure we can see all angles are less than 90° and it has two equal sides and these are the property of acute angle and isosceles triangle.
(b) Right-angled scalene triangle
As the triangle has one right angle and three unequal sides and these are the property of right-angled and scalene triangle.
(c) Obtuse-angled and isosceles triangle
As we can see one angle is greater than 90° and it has two equal sides and these are the property of obtuse angle and isosceles triangle.
(d) Right-angled and isosceles triangle
As it has one angle of 90° and two equal sides and these are the property of right-angled and isosceles triangle.
(e) Acute-angled and equilateral triangle
As in the figure we can see all angles are less than 90° and it has all equal sides and these are the property of acute angle and equilateral triangle.
(f) Obtuse-angled and scalene triangle
As we can see one angle is greater than 90° and three unequal sides and according to the property of triangles only obtuse-angled and scalene triangle has these property.