Recognising line symmetry and rotational symmetry will ... 50° and 80° is an acute-angled triangle. Image caption, A scalene triangle with all angles less than 90° is an acute-angled triangle.

Three lines of symmetry on an equilateral triangle. Right-angled triangles follow the same rules as other triangles. It's not the right angle that matters but whether the triangle is scalene or ...

You may hear students say words like ‘paralyzed’ triangle for isosceles and equilateral triangles after noticing the restrictive movements of these triangles upon dragging. Properties of symmetry: - ...