Not necessarily, except rotational symmetry of order 1.
a right triangle
yes * * * * * Usually, no. Only isosceles right angled triangles have a line of symmetry.
It can have, but only if the two smaller angles are 45 degrees, then there is symmetry about the centre-line.
It can have a line of symmetry but most have none. Not necessarily. In most cases it would have none.
None.
None.
I think none. In fact the only triangle that I believe has any rotational symmetry is an equilateral triangle.
3
Not necessarily, except rotational symmetry of order 1.
a right triangle
yes * * * * * Usually, no. Only isosceles right angled triangles have a line of symmetry.
The modern answer is that if the shape only fits once onto the original when rotated 360o it has no rotational symmetry. A right triangle only fits once when rotated 360o so it has no rotational symmetry.
A scalene triangle that is not right angled.
None normally but if it is a right angle isosceles triangle it will have 1 line of symmetry
it has only one line of symmetry.
This could be either an isosceles triangle or a right angled triangle.