A symmetrical shape. There are many different shapes that have one or more lines of symmetry and there is no other name associated with them as a group.
a shape with a line of symmetry
symmetrical
The 2D shape which has one line of symmetry is the trapezium.
An isosceles triangle has one line of symmetry
Not necessarily.
no
square
How about an isosceles triangle which has one line of symmetry
the shape is a heart.
An isosceles triangle and a kite have only one line of symmetry.
An isosceles triangle
Every right circular cone, conic section, and regular polygon has at least one line of symmetry.