It has 1 line of symmetry
1 line of symmetry.
1
it has only one line of symmetry.
3
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
Right-angled Trapezium
rectangle
For a right isosceles triangle (45-45-90), there is one line of symmetry that bisects the hypotenuse. For all other right triangles, there are zero lines of symmetry.
0 zip zilch nada none
An irregular quadrilateral.