How many lines of symmetry does a triangle have?

A triangle can have 3, 1, or no lines of symmetry. The number of the lines of symmetry varies, and this depends on the type of quadrilateral. A circle has an infinite number of lines of symmetry because an infinite number of lines can be drawn passing through its centre. How Can We Find Whether a Shape has a Line of Symmetry or not?

What is a line of symmetry?

You would call this the line of symmetry. If you put a mirror on this line, you would see the whole shape in the reflection. That’s why a line of symmetry is sometimes called the mirror line. Sometimes you can fold a shape in half, and if it fits into itself perfectly with no overlaps you have found a line of symmetry.

How many lines of symmetry does a two-dimensional shape have?

Different two-dimensional shapes have different numbers of lines of symmetry. The three lines of symmetry are shown in this slideshow. Three lines of symmetry on an equilateral triangle. Shaded area shows vertical symmetry. Shaded area shows reflection symmetry about one sloping line.

What shapes have no lines of symmetry?

On the other hand, some shapes have no lines of symmetry. For example, a circle and oval both have no lines of symmetry, because they’re symmetrical all around their centres! Here’s a quick guide to how many lines of symmetry the most common 2D shapes have.